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Author Topic: hhop  (Read 215093 times)

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hhop gen 3 Specific Gravity Pump 8)


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hhop gen 3 Specific Gravity Pump  8)

1) Spring loaded NRV has a cracking pressure slightly > a, which is the force exerted on the NRV outlet by the weight of water in the lower chamber (below the piston face), designated a.

2) Water reservoir inlet valve opens and upper chamber fills to weight b, which is = a, and the cracking pressure of the magnet supporting weight b. The seal prevents chamber b from transmitting hydraulic pressure to chamber a, which would open the NRV outlet prematurely.

3) Weight b pumps fluid a, leveraging pascals hydraulic principle and driving the turbine alternator to produce electricity. 1.5 psi of fluid pressure is lost as work done pumping through 1 meter of height.

4) Chamber b has assumed the position previously occupied by chamber a. The piston is now injected with hho and the water is displaced, reducing the density of the piston body which will now rise. Hydraulic pressure equalisation valve opens to aid piston seal liquid flow resistance.

5) Piston ascends being more buoyant than the water it is submerged in.

6) Piston seals with a magnetic holding force = a. hho exhaust valve opens and the piston bleeds hydraulically. Pressure equalisation valve closes, water reservoir inlet valve opens and the cycle repeats.


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Single Acting Piston Seals

http://www.martins-rubber.co.uk/products/seals/piston-seals/single-acting-piston-seals/

Single Acting Piston Seals of all types and materials, in all sizes.

The function of a Single Acting Piston Seal is to contain pressure on one side of a piston without leakage and therefore allow maximum effort to be applied to moving the piston along the bore of a cylinder. Single Acting pistons only contain pressure on one side of the piston, and the seal is required to retain pressure from that direction, which then moves the piston along the cylinder, in a “Single Action”. The return stroke of the cylinder must be powered by mechanical energisation or possibly a simple gravity return. Consideration needs to be given to the pressures expected, the friction losses acceptable, whether a single acting capability is required, and whether the piston head is integral or split.

The function of a Single Acting Piston Seal is to contain pressure on one side of a piston without leakage and therefore allow maximum mechanical effort to be applied to moving the piston along the bore of a cylinder. They can be driven either hydraulically or pneumatically, with appropriate seal designs for each system, and application. The seal is intended to prevent leakage across the piston and thus maximise the efficiency of system; pressure is applied in one direction only, to drive the ram rod that the piston is fixed to along the cylinder in a “Single Action”. The return stroke of the ram, once pressure is released, must be powered by another mechanical means such as a spring if necessary, or perhaps a simple gravity return driven by the mass that the ram has moved (or manipulating the specific gravity field to reset the piston). Individual seal profile designs show specific behaviours and performance, which need to be in line with the application´s requirement. The material chosen will also influence the choice of seal profile. When determining the best seal design and material for a particular application, consideration needs to be given to the pressures expected, the friction losses acceptable, and whether the piston head is integral or split.

The design of the piston head is important, as this will dictate what types of seal profile and material can be used in the application. Many high pressure systems require very stiff, robust seals and the associated guide rings to control the action of the piston. In such cases, it is usual to split the piston into several parts so that the seals do not need to be stretched over the piston head and snapped into place, but can simply be assembled in place and the piston head bolted on to the ram rod with a securing nut, once fully built up.



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Hydraulic machinery

https://en.wikipedia.org/wiki/Hydraulic_machinery

Hydraulic machines are machinery and tools that use liquid fluid power to do simple work. Heavy equipment is a common example.

In this type of machine, hydraulic fluid is transmitted throughout the machine to various hydraulic motors and hydraulic cylinders and which becomes pressurised according to the resistance present. The fluid is controlled directly or automatically by control valves and distributed through hoses and tubes.

The popularity of hydraulic machinery is due to the very large amount of power that can be transferred through small tubes and flexible hoses, and the high power density and wide array of actuators that can make use of this power.

Hydraulic machinery is operated by the use of hydraulics, where a liquid is the powering medium.

Force and torque multiplication

A fundamental feature of hydraulic systems is the ability to apply force or torque multiplication in an easy way, independent of the distance between the input and output, without the need for mechanical gears or levers, either by altering the effective areas in two connected cylinders or the effective displacement (cc/rev) between a pump and motor. In normal cases, hydraulic ratios are combined with a mechanical force or torque ratio for optimum machine designs such as boom movements and trackdrives for an excavator.

Accumulators

Accumulators are a common part of hydraulic machinery. Their function is to store energy by using pressurized gas. One type is a tube with a floating piston. On one side of the piston is a charge of pressurized gas, and on the other side is the fluid. Bladders are used in other designs. Reservoirs store a system's fluid.

Examples of accumulator uses are backup power for steering or brakes, or to act as a shock absorber for the hydraulic circuit.

https://en.wikipedia.org/wiki/Hydraulic_accumulator

The first accumulators for Armstrong's hydraulic dock machinery were simple raised water towers. Water was pumped to a tank at the top of these towers by steam pumps. When dock machinery required hydraulic power, the hydrostatic head of the water's height above ground provided the necessary pressure.

These simple towers were extremely tall. One of the best known, Grimsby Dock Tower opened in 1852, is 300 feet (91 m) tall. The size of these towers made them expensive to construct. By the time Grimsby was opened, it was already obsolete as Armstrong had developed the more complex, but much smaller, weighted accumulator. These simple tower accumulators were constructed for less than a decade. In 1892 the original Grimsby tower's function was replaced by a smaller weighted accumulator on an adjacent dock, although the tower remains to this day as a well-known landmark.

Raised weight

A raised weight accumulator consists of a vertical cylinder containing fluid connected to the hydraulic line. The cylinder is closed by a piston on which a series of weights are placed that exert a downward force on the piston and thereby energizes the fluid in the cylinder. In contrast to compressed gas and spring accumulators, this type delivers a nearly constant pressure, regardless of the volume of fluid in the cylinder, until it is empty. (The pressure will decline somewhat as the cylinder is emptied due to the decline in weight of the remaining fluid.)

A working example of this type of accumulator may be found at the hydraulic engine house, Bristol Harbour.[1] The external accumulator was added around 1920. The water is pumped from the harbour into a header tank and then fed by gravity to the pumps. The working pressure is 750 psi (5.2 MPa, or 52 bar) which is used to power the cranes, bridges and locks of Bristol Harbour.

The original operating mechanism of Tower Bridge, London, also used this type of accumulator. Although no longer in use, two of the six accumulators may still be seen in situ in the bridge's museum.

Regent's Canal Dock, now named Limehouse Basin has the remains of a hydraulic accumulator, dating from 1869, a fragment of the oldest remaining such facility in the world, the second at the dock, which was installed later than that at Poplar Dock, originally listed incorrectly as a signalling cabin for the London and Blackwall Railway, when correctly identified, it was restored as a tourist attraction by the now defunct London Docklands Development Corporation. Now owned by the British Waterways Board, it is open for large groups on application to the Dockmaster's Office at the basin and on both the afternoons of London Open House Weekend, held on the third weekend of September each year.

London had an extensive public hydraulic power system from the mid-nineteenth century finally closing in the 1970s with 5 hydraulic power stations, operated by the London Hydraulic Power Company. Railway goods yards and docks often had their own separate system.

Functioning of an accumulator

In modern, often mobile, hydraulic systems the preferred item is a gas charged accumulator, but simple systems may be spring-loaded. There may be more than one accumulator in a system. The exact type and placement of each may be a compromise due to its effects and the costs of manufacture.

An accumulator is placed close to the pump with a non-return valve preventing flow back to the pump. In the case of piston-type pumps this accumulator is placed in the ideal location to absorb pulsations of energy from the multi-piston pump. It also helps protect the system from fluid hammer. This protects system components, particularly pipework, from both potentially destructive forces.

An additional benefit is the additional energy that can be stored while the pump is subject to low demand. The designer can use a smaller-capacity pump. The large excursions of system components, such as landing gear on a large aircraft, that require a considerable volume of fluid can also benefit from one or more accumulators. These are often placed close to the demand to help overcome restrictions and drag from long pipework runs. The outflow of energy from a discharging accumulator is much greater, for a short time, than even large pumps could generate.

An accumulator can maintain the pressure in a system for periods when there are slight leaks without the pump being cycled on and off constantly. When temperature changes cause pressure excursions the accumulator helps absorb them. Its size helps absorb fluid that might otherwise be locked in a small fixed system with no room for expansion due to valve arrangement.

The gas precharge in an accumulator is set so that the separating bladder, diaphragm or piston does not reach or strike either end of the operating cylinder. The design precharge normally ensures that the moving parts do not foul the ends or block fluid passages. Poor maintenance of precharge can destroy an operating accumulator. A properly designed and maintained accumulator should operate trouble-free for years.


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hhop gen 3 Basic Theory Information 8)


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Water tower

https://en.wikipedia.org/wiki/Water_tower

A water tower is an elevated structure supporting a water tank constructed at a height sufficient to pressurize a water supply system for the distribution of potable water, and to provide emergency storage for fire protection. In some places, the term standpipe is used interchangeably to refer to a water tower, especially one with tall and narrow proportions.[1] Water towers often operate in conjunction with underground or surface service reservoirs, which store treated water close to where it will be used.[2] Other types of water towers may only store raw (non-potable) water for fire protection or industrial purposes, and may not necessarily be connected to a public water supply.

Water towers are able to supply water even during power outages, because they rely on hydrostatic pressure produced by elevation of water (due to gravity) to push the water into domestic and industrial water distribution systems; however, they cannot supply the water for a long time without power, because a pump is typically required to refill the tower. A water tower also serves as a reservoir to help with water needs during peak usage times. The water level in the tower typically falls during the peak usage hours of the day, and then a pump fills it back up during the night. This process also keeps the water from freezing in cold weather, since the tower is constantly being drained and refilled.[citation needed]

Although the use of elevated water storage tanks has existed since ancient times in various forms, the modern use of water towers for pressurized public water systems developed during the mid-19th century, as steam-pumping became more common, and better pipes that could handle higher pressures were developed. In Great Britain, standpipes consisted of tall, exposed, inverted u-shaped pipes, used for pressure relief and to provide a fixed elevation for steam-driven pumping engines which tended to produce a pulsing flow, while the pressurized water distribution system required constant pressure. Standpipes also provided a convenient fixed location to measure flow rates. Designers typically enclosed the riser pipes in decorative masonry or wooden structures. By the late 19th-Century, standpipes grew to include storage tanks to meet the ever-increasing demands of growing cities.[1]

Many early water towers are now considered historically significant and have been included in various heritage listings around the world. Some are converted to apartments or exclusive penthouses.[3] In certain areas, such as New York City in the United States, smaller water towers are constructed for individual buildings. In California and some other states, domestic water towers enclosed by siding (tankhouses) were once built (1850s–1930s) to supply individual homes; windmills pumped water from hand-dug wells up into the tank.

Design and construction

A variety of materials can be used to construct a typical water tower; steel and reinforced or prestressed concrete are most often used (with wood, fiberglass, or brick also in use), incorporating an interior coating to protect the water from any effects from the lining material. The reservoir in the tower may be spherical, cylindrical, or an ellipsoid, with a minimum height of approximately 6 metres (20 ft) and a minimum of 4 m (13 ft) in diameter.[citation needed] A standard water tower typically has a height of approximately 40 m (130 ft).

Pressurization occurs through the hydrostatic pressure of the elevation of water; for every 10.20 centimetres (4.016 in) of elevation, it produces 1 kilopascal (0.145 psi) of pressure. 30 m (98.43 ft) of elevation produces roughly 300 kPa (43.511 psi), which is enough pressure to operate and provide for most domestic water pressure and distribution system requirements.
Shooter's Hill water tower is a local landmark in London, United Kingdom. Water towers are common around London suburbs.

The height of the tower provides the pressure for the water supply system, and it may be supplemented with a pump. The volume of the reservoir and diameter of the piping provide and sustain flow rate. However, relying on a pump to provide pressure is expensive; to keep up with varying demand, the pump would have to be sized to meet peak demands. During periods of low demand, jockey pumps are used to meet these lower water flow requirements. The water tower reduces the need for electrical consumption of cycling pumps and thus the need for an expensive pump control system, as this system would have to be sized sufficiently to give the same pressure at high flow rates.

Very high volumes and flow rates are needed when fighting fires. With a water tower present, pumps can be sized for average demand, not peak demand; the water tower can provide water pressure during the day and pumps will refill the water tower when demands are lower.

Using wireless sensor networks to monitor water levels inside the tower allows municipalities to automatically monitor and control pumps without installing and maintaining expensive data cables.[4]

I have put one water tower 'b' on top of another water tower 'a'.. I have isolated the hydrostatic pressure equalisation potential for both chambers, from each other via the piston. System open to atmospheric pressure on both columns. Chamber b acts as a Mass only, gravity filled. Chamber a always has hydrostatic pressure, with bias set by NRV resistance (psi cracking pressure). 1.5 psi loss for every 1 meter of output column elevation, therefore pressure loss through elevation (pumping vertically) considered negligible in a 1 meter high system. Leverage Pascal's principle to extend run time and increase pressure at the expense of flow rate. The electrical energy required to complete the electrolytic reset of the hollow piston will become a constant, and the run time on the turbine at a given RPM will also, so when they match you have COP=1. Increase the sizes of reservoirs a and b and extend the run time of the the water wheel alternator therefore COP>1 becomes a variable. The specific gravity field provides the force to reset the piston, with only minimal interaction of the medium it is submersed in (liquid water).

Pascal's law

https://en.wikipedia.org/wiki/Pascal%27s_law

Pascal's law or the principle of transmission of fluid-pressure (also Pascal's Principle[1][2][3]) is a principle in fluid mechanics that states that pressure exerted anywhere in a confined incompressible fluid is transmitted equally in all directions throughout the fluid such that the pressure variations (initial differences) remain the same.[4] The law was established by French mathematician Blaise Pascal.[5]

If a U-tube is filled with water and pistons are placed at each end, pressure exerted against the left piston will be transmitted throughout the liquid and against the bottom of the right piston. (The pistons are simply "plugs" that can slide freely but snugly inside the tube.) The pressure that the left piston exerts against the water will be exactly equal to the pressure the water exerts against the right piston. Suppose the tube on the right side is made wider and a piston of a larger area is used; for example, the piston on the right has 50 times the area of the piston on the left. If a 1 N load is placed on the left piston, an additional pressure due to the weight of the load is transmitted throughout the liquid and up against the larger piston. The difference between force and pressure is important: the additional pressure is exerted against the entire area of the larger piston. Since there is 50 times the area, 50 times as much force is exerted on the larger piston. Thus, the larger piston will support a 50 N load - fifty times the load on the smaller piston.

Forces can be multiplied using such a device. One newton input produces 50 newtons output. By further increasing the area of the larger piston (or reducing the area of the smaller piston), forces can be multiplied, in principle, by any amount. Pascal's principle underlies the operation of the hydraulic press. The hydraulic press does not violate energy conservation, because a decrease in distance moved compensates for the increase in force. When the small piston is moved downward 10 centimeters, the large piston will be raised only one-fiftieth of this, or 0.2 centimeters. The input force multiplied by the distance moved by the smaller piston is equal to the output force multiplied by the distance moved by the larger piston; this is one more example of a simple machine operating on the same principle as a mechanical lever.

Pascal's principle applies to all fluids, whether gases or liquids. A typical application of Pascal's principle for gases and liquids is the automobile lift seen in many service stations (the hydraulic jack). Increased air pressure produced by an air compressor is transmitted through the air to the surface of oil in an underground reservoir. The oil, in turn, transmits the pressure to a piston, which lifts the automobile. The relatively low pressure that exerts the lifting force against the piston is about the same as the air pressure in automobile tires. Hydraulics is employed by modern devices ranging from very small to enormous. For example, there are hydraulic pistons in almost all construction machines where heavy loads are involved.


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http://www.rockyhydro.com/Micro-Hydro_Basics.php

Converting the Energy - The device used to capture the energy of the flowing water is the turbine.  There are many different types of turbines, but they can be broken down into two different groups - impulse and reaction.

Impulse turbines such as a pelton wheel or a turgo work best when there is a relatively small amount of flow but a relatively large amount of head.  The high pressure water stream hits the turbine paddle or spoon, forcing it to turn.  The spoons of a turgo and pelton turbine are curved, so the water doesn't just hit a paddle and fall away, the water actually does a 180 degree turn.  The extra force of causing the water to completely change directions makes the turbine spin even faster.

https://en.wikipedia.org/wiki/Micro_hydro

Head and flow characteristics

Microhydro systems are typically set up in areas capable of producing up to 100 kilowatts of electricity.[3] This can be enough to power a home or small business facility. This production range is calculated in terms of "head" and "flow". The higher each of these are, the more power available. "Head" is the pressure measurement of falling water expressed as a function of the vertical distance the water falls.[3] This change in elevation is usually measured in feet or meters. A drop of at least 2 feet is required or the system may not be feasible.[4] When quantifying head, both gross and net head must be considered.[4] Gross head approximates power accessibility through the vertical distance measurement alone whereas net head subtracts pressure lost due to friction in piping from the gross head.[4] "Flow" is the actual quantity of water falling from a site and is usually measured in gallons per minute, cubic feet per second, or liters per second.[5]

Power from such a system can be calculated by the equation P=Q*H/k, where Q is the flow rate in gallons per minute, H is the head loss, and k is a constant of 5,310 gal*ft/min*kW.[citation needed] For instance, for a system with a flow of 500 gallons per minute and a head loss of 60 feet, the theoretical maximum power output is 5.65 kW. The system is prevented from 100% efficiency (from obtaining all 5.65 kW) due to the real world, such as: turbine efficiency, friction in pipe, and conversion from potential to kinetic energy. Turbine efficiency is generally between 50-80%, and pipe friction is accounted for using the Hazen–Williams equation.[citation needed]

To account for efficiency, simply multiply the theoretical by the efficiency. In this example, if the plant's efficiency was 90%, then 5.65 kW*0.9= 5.085 kW.

Advantages and disadvantages

System advantages

Microhydro power is generated through a process that utilizes the natural flow of water.[12] This power is most commonly converted into electricity. With no direct emissions resulting from this conversion process, there are little to no harmful effects on the environment, if planned well, thus supplying power from a renewable source and in a sustainable manner. Microhydro is considered a "run-of-river" system meaning that water diverted from the stream or river is redirected back into the same watercourse.[13] Adding to the potential economic benefits of microhydro is efficiency, reliability, and cost effectiveness.[13]

System disadvantages

Microhydro systems are limited mainly by characteristics of the site. The most direct limitation comes from small sources with minuscule flow. Likewise, flow can fluctuate seasonally in some areas.[13] Lastly, though perhaps the foremost disadvantage is the distance from the power source to the site in need of energy.[13] This distributional issue as well as the others are key when considering using a microhydro system.

Weight-Loaded Accumulators

http://www.accumulators-hyd.com/accumulators.html

The first real accumulators were weight-loaded types and these are still applicable where there is considerable headroom available with overhead gantries or lifting mechanisms plus factory space at a reasonable cost. They are nearly always used in a ring main system that supplies a department or complete factory with its hydraulic power.

Weight-loaded accumulators continue to be used to meet heavy industrial requirements and large units usually employ water as the fluid. The large weight-loaded accumulator offers the advantage of extremely high capacity at relatively low cost per unit volume. Construction is rugged and durable, and the units are capable of accommodating shock loads. Only simple control gear is necessary.

The disadvantages of a weight-loaded accumulator are:

    The accumulator is extremely bulky and heavy and thus could not be considered where space or weight saving is an important factor.
    Pressure output is not constant, largely due to the effects of seal friction and inertia.
    Certain restrictions are imposed on delivery, largely due to limitations on falling speed to minimize hydraulic shock.
    The seals themselves may pose problems, both in providing adequate sealing with low friction when they are used with such a low viscosity fluid as water, and when expected to give long seal life. Where such an accumulator is used as a central source, failure of the seals would result in loss of supply to all the hydraulic machines on the circuit.

The basic design of a weight-loaded accumulator is shown in Fig. 1. A heavy walled cylinder is mounted vertically on a substantial base and carries a ram. A crosshead is attached to the top of the ram, from which is slung a weight box. This is filled with any high density waste, such as ballast, iron scrap, concrete, etc. Alternatively, in the case of smaller units, special made weights may be slung from the ends of the crosshead.

There are two main types, depending on the method of constraining the weights or weight box. On a self-guided design the weight case is provided with internal guides. On externally-guided designs the weight case is constrained against radial movement by external guides or channels, usually mounted on a steel structure. The latter type is normally preferred to large high pressure accumulators to minimize bending stresses.

The ram is raised by pumping fluid (water) into the cylinder. Once raised, the fluid in the cylinder is pressurized by the combination of the weights and ram acting on the cross sectional area of the fluid column. The theoretical pressure available is thus given by:

Pressure (Bar) = 0.03Wt

D2   

Where Wt = total weight in kilograms

D = ram diameter in centimeters

Pressure (psi) = 1.274Wt

D2

Where Wt = total weight in pounds

D = ram diameter in inches

In practice the nominal pressure available will be a little less, due to seal friction opposing downward motion. Pressure variations are also likely to occur with differences or variations in falling speed. Thus a pressure variation of 5% is likely to be experienced with a maximum falling speed of 0.3 meters per second (1 foot per second), but may be higher with higher falling speeds. Momentary peak pressures may also be higher or lower than the nominal pressure by an appreciable amount, depending on the rate of deceleration or acceleration of the ram, respectively.

Falling speed can be controlled by the stroke/bore ratio of the ram. A stroke/bore ratio of between 10 and 15 is commonly adopted for accumulators working up to 105 Bar (1500psi), although higher ratios are generally to be preferred for higher pressures. This, however, increases the problem of obtaining mechanical rigidity and also increases the overall height of the accumulator. This could make it unsuitable for indoor installation. As a rough guide, the overall height of a weight-loaded accumulator is at least twice the stroke.

Cast iron cylinders are commonly employed for accumulators working up to 105 Bar (1500psi). Cast steel or forged steel cylinders are used for higher pressures. Honed bores are required, although satisfactory performance may be obtained with rougher bores using leather seals. Rams may be made from cast iron (the original choice and still widely employed), but preferably chrome plated. Stainless steel or alloy steel rams are more usual on smaller sizes of modern weight-loaded accumulators.

Variations in the overall design include the type with a fixed ram and sliding cylinder, and also the differential weight-loaded accumulator. The latter is essentially a lower capacity device, but one capable of providing very high fluid pressures with a relatively low loaded weight. Construction takes the form of a fixed ram with the lower part fitted with a sleeve to increase its diameter. The cylinder slides over the ram and is fitted with weights, the sliding system being either internally or externally guided. The difference in ram diameter and sleeve diameter is relatively small, providing a substantial pressure amplifying effect – Fig. 2.

Control of a weight-loaded accumulator is essentially simple and straightforward. Normal safety devices employed with a continuous running pump include a relief valve which opens automatically to relieve pressure should the ram be raised beyond its normal upper position, and a bypass valve to relieve the system of pressure build-up should all controls fail with the pump still working. If the pump is operated on a "stop-start" basis, pump switching can be controlled mechanically by tappets on the moving assembly operating the pump starter or pump motor at the bottom of the stroke and stopping the pump when the ram reaches the top of its stroke. A typical control circuit is shown in Fig. 3 with automatic starting and stopping of the pump, together with an offloading valve to reduce peak load on starting up the pump.

hhop gen 3 is designed to use gravitational energy as the input and provide electrical COP>1 output with hho produced at the gas exhaust as a waste product  8)


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http://hydraulicspneumatics.com/other-technologies/chapter-16-accumulators

Weight loaded: All gas-charged accumulators lose pressure as fluid discharges. This is because the nitrogen gas was compressed by incoming fluid from the pump and the gas must expand to push fluid out. The weight-loaded accumulator in Figure 16-1 does not lose pressure until the ram bottoms out. Thus 100% of the fluid is useful at full system pressure. The major drawback to weight-loaded accumulators is their physical size. They take up a lot of space and are very heavy if much volume is required. They work well in central hydraulic systems because there usually is room for them in the power unit area. However, central hydraulic systems are falling out of favor, so only a few facilities use weight-loaded accumulators. (Rolling mills are one application where space to place large items is not a problem.) Note that there is often a long dwell time to fill these monsters.

http://www.ehp-eg.com/hydraulic-training/hydraulic-accumulators/

The weight loaded accumulator is the only hydraulic accumulator,where the oil pressure remains constant regardless of amount filled, however a large volume of space is required for the weight.

If the Weight (Force) of chamber 'b' is a liquid, Mass can be moved easily by the Force of Gravity from a higher potential to a lower potential.

The piston can be lightweight plastic and being hollow contains a chamber that liquid water can be displaced from.

The hollow piston at the bottom of the stroke can be reset by a Force provided by the Specific Gravity Field differential.


http://www.tobul.com/index.php?option=com_content&task=view&id=13&Itemid=27


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Gravity accumulator

http://hydraulicstraining.blogspot.co.uk/2011/10/types-of-accumulator.html

The Weight-Loaded or Gravity accumulator, shown in Fig. 4–8, consists of a long, finely ground and polished vertical steel cylinder that is fitted with a long, close fitting, smooth finished piston. A sealing device of some type is fitted into the cylinder wall to prevent fluid from leaking past the piston. Weights are mounted or placed on the piston to maintain a constant fluid pressure with in the cylinder and the remainder of the system. The amount of weight depends on the system pressure. The piston is prevented from over traveling by limit switches that turn the pump off when the level is too high and turn the pump on when the level becomes low.

The fluid capacity of most weight – loaded accumulators does not exceed 250 cubic inches (slightly over one gallon). Weight – loaded accumulators are used infrequently because they are large, heavy, costly, and sluggish. Their response to changes in fluid demand is slow especially during high input surges because of the large mass of the weights and the frictional drag of the pressure seals.

hhop gen 3 by comparison has a lightweight neutrally buoyant hollow piston.

Understanding Hydrostatic Pressure and Pascal's Law

http://hydraulicstraining.blogspot.co.uk/2011/10/understanding-hydrostatic-pressure-and.html

Fig. 1-4. shows a number of differently shaped, connected, open containers. Because liquid seek their own level, the liquid level as shown is at the same height in each container. This occurs because pressure is developed, with in a liquid, by the weight of the liquid above. If the liquid level in any one container were to be higher than that in any of the other containers, the higher pressure at the bottom of this container would cause some liquid to flow into the container having the lower liquid level. Also, the pressure of the liquid at any level (such as line A) is the same in each containers. Pressure increases because of the weight of the fluid. The farther down from the surface, the more pressure is created. This illustrates that the volume of liquid contained in a vessel has nothing to do with the pressure at the bottom of the vessel.

Pascal's Law.
The previous paragraph has just shown what happens to fluid in open containers. When pressure is exerted on a confined liquid, the pressure is transmitted equally in all directions through the liquid, as shown in Fig. 1-5. If the hammer strikes the solid block of wood, the force is only transmitted in a straight line. But if the hammer strikes a fluid, force is transmitted in all directions. Similarly, the pressure exerted on the liquid in Fig. 1-6. is equally distributed by the liquid throughout the system. Note how the hydraulic pressure in the tubing and containers acts with equal force in all directions.

hhop gen 3 chamber 'a' always has hydrostatic pressure as its working principle, chamber 'b' has only a weight force vector until it becomes chamber 'a' after hollow piston buoyancy reset.



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MICRO-HYDRO INSTALLATION SIZING (PELTON AND TURGO WHEEL TURBINES)

http://www.pumpfundamentals.com/micro-hydro.htm

A very useful page to learn about micro hydro technology courtesy of the pumpfundamentals.com website :)

You will have to adjust your thinking to adapt to hhop gen 3 technology, much larger heads will be available than from a typical stream (the weight loaded accumulator can deliver very high pressures). High pressure (high velocity) with low flow extends turbine run time at the expense of power produced, the benefit is that approximately the same amount of energy will be produced overall from the power stroke but the longer run time / lower power configuration will allow you to easier match the refill / reset time of the second hhop gen 3, running on opposing cycle. Water erosion of the spoons will increase with a faster velocity jet, but higher flow lower pressure demands more SGP modules to meet system requirements..

Keep the turbine running 24/7 is the goal, add hhop gen 3's to meet flow requirements :)
« Last Edit: 2015-07-22, 21:54:44 by evolvingape »


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http://firefightermath.org/

Firefighter Math: Self-Paced Math Course

This self-paced math course refreshers firefighters' knowledge of basic math concepts and tools necessary for making math calculations in the field. Topics include calculating tank volumes and flow rates, determining pump pressure and friction loss, understanding maps and location coordinates, and estimating slope. Additionally, the course presents information on calculating flame length, flame height, midflame windspeed, and other variables related to wildland firefighting efforts.

Squirt Water

3.1 Volume or Capacity

http://firefightermath.org/index.php?option=com_content&view=article&id=27&Itemid=126

Volume is used to indicate the capacity of a tank or container. It is used by firefighters to answer questions like "How much water is left in the tank?" and "At 15 gallons per minute (gpm), how many more minutes before the tank is empty?"

3.2 Volume of Water in Hose

http://firefightermath.org/index.php?option=com_content&view=article&id=29&Itemid=43

Volume of a Hose

The volume of a hose allows an estimate of how much water can be delivered to the fire and is important in firefighting. The hose diameter is usually given in inches, with length in feet. The volume of a hose can be computed using the equation for volume of a cylinder in Section 3.1.

3.3 Friction Loss in Fire Hose

http://firefightermath.org/index.php?option=com_content&view=article&id=30&Itemid=44

Friction Loss

Friction loss is the resulting resistance as water (fluid) moves along the inside wall of either a hose, pipe, or hose fittings.

Points to remember about friction loss:

    Friction loss increases as flow (gpm) increases.
    Total friction loss varies with length -- the greater the length, the higher the friction loss.
    Friction losses on reeled hose average about 21 percent more than for straight hose lays.
    Friction loss is nearly independent of pressure.
    Friction loss varies with type, lining, weave, quality, and age of the hose.
    Friction loss increases 4 times for each doubling of water flow. Reducing the diameter of a hose by 1/2 will increase the friction loss by a factor of 32 for the same flow.

To account for friction loss, the pressure at which the pump is working must be increased. The pump pressure must also be or decreased to compensate for the head loss or gain, to produce the desired nozzle pressure.

3.4 Calculating Engine Pump Pressures

http://firefightermath.org/index.php?option=com_content&view=article&id=31&Itemid=45

Pump Pressure

To achieve a desired nozzle pressure (DNP), a few factors must be considered. First, you must note the head loss (HL) or head gain (HG). Water head is the height of the water column (lift) due to imposing pressure. The head pressure is positive (gain) if the hose lay is downhill because the force of gravity is helping push the water down, consequently increasing the pressure. The head pressure is negative (loss) if the hose lay is uphill, since the force of gravity is pulling the water down, when it needs to be pumped up. Table 3.1 indicates that 1 foot of water head or lift produces 0.5 pounds per square inch of pressure. On that same note, 1 pound per square inch can produce 2 feet of water head). For every foot uphill or downhill, there is a change of 0.5 pounds per square inch of pressure. Note that this measurement represents the height of the hose (elevation) and not the length of the hose.

3.5 Drafting Guidelines

http://firefightermath.org/index.php?option=com_content&view=article&id=32&Itemid=46

Drafting Guidelines

It is important to know the difference in elevation between the pump and the water source when drafting water from a pond or stream. When drafting water, the air at atmospheric pressure is removed from the hose line, creating a vacuum (negative pressure) within the pump chamber. The atmospheric pressure (weight of air) on the water's surface forces the water up through the suction hose to the pump.

The maximum height to which an engine or pump can lift water is determined by the atmospheric pressure. At sea level, the atmosphere exerts an average pressure of 14.7 pounds per square inch (psi). Atmospheric pressure will vary due to changes in the weather. However, these changes tend to moderate themselves so that the average pressure will tend to go back toward 14.7 pounds per square inch. That is why it is safe to use this value of 14.7 pounds per square inch as a constant for calculations.

3.6 Flow Rates

http://firefightermath.org/index.php?option=com_content&view=article&id=33&Itemid=47

Flow Rates

Flow rates describe the speed at which water is flowing. They are described in gallons per minute (gpm). The following test is a simple way to observe a flow rate.

Use a large drum with a marked level to indicate a pre-measured 50-gallon volume. Begin filling the drum with a hose and at the instant that the water begins to fill the tank, start timing how long it takes with a precise stop watch (preferably to 1/100 of a minute). When the water level reaches the marked line, take the hose away, and stop timing. To calculate the flow rate of the water through the hose, divide the total volume by the total time it took to reach that volume. Suppose it took 3.55 minutes.

50 gallons per 3.55 minutes (50/3.55)
50 ÷ 3.55 = 14.08
Flow rate = 14.08 gpm

If the stop watch has only seconds and minutes, the seconds can be converted into fractions (parts) of minutes. There are 60 seconds in 1 minute.


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How much electricity can a micro hydro system produce?

http://info.cat.org.uk/questions/hydro/how-much-electricity-can-micro-hydro-system-produce

A good hydro site depends on the 'head' of water (the vertical drop) and the flow rate. To estimate the energy in a water source, multiply the flow (in litres per second) by the head (in metres) by 10 (acceleration due to gravity). Halve the result, to account for losses and inefficiencies, to get an idea of potential power generation (in watts).

Flow x Head x 10 x 0.5 = Potential power generation in Watts

As this equation makes clear, a greater head will provide more power. Also, as a high head turbine will spin very quickly, there may be no need for complex gearboxes or belts.

Once you've worked out the capacity of the turbine in kW, you'll then need estimates of how often you can run the turbine (e.g. hours per day or per year) to estimate the energy output over time.

For example, a 5kW turbine running continuously for 24 hours will produce: 5kW x 24 hours = 120 kilowatt-hours (kWh).

Most micro-hydro schemes are ‘run-of-river’ - they don’t have a reservoir and only take water from the stream when it is available. You usually need a drop of over 10 metres for a scheme to be viable. High head ‘Pelton’ turbines are comparatively cheap, easy to install and work well in fluctuating flow. Crossflow turbines are more suitable for lower heads. Other turbines are available; their suitability depends on a combination of the available head and flow of water.

How much power could I generate?

http://www.renewablesfirst.co.uk/hydro-learning-centre/how-much-power-could-i-generate/

If you mean power, read on. If you mean energy (which is what you sell) read here. Power is the rate of producing energy. Power is measured in Watts (W) or kiloWatts (kW). Energy is what is used to do work and is measured in kilowatt-hours (kWh) or megawatt-hours (MWh).

In simple terms, the maximum power output is entirely dependent on how much head and flow is available at the site, so a tiny micro-hydro system might produce just 2 kW, whereas a large utility-scale hydro system could easily produce hundreds of Megawatts (MW). To put this in context, a 2 kW hydropower system could satisfy the annual electrical energy needs of two ‘average’ UK homes, whereas a utility-scale 200 MW system could supply 200,000 average UK homes.

If you don’t mind equations the easiest way to explain how much hydropower you could generate is to look at the equation for calculating hydro power:

    P = m x g x Hnet x System efficiency

Where?

P = Power, measured in Watts (W).
m = Mass flow rate in kg/s (numerically the same as the flow rate in litres/second because 1 litre of water weighs 1 kg).
g = the gravitational constant, which is 9.81 m/s2.
Hnet = the net head. This is the gross head physically measured at the site, less any head losses. To keep things simple head losses can be assumed to be 10%, so Hnet is the gross head x 90%.
System efficiency = the product of all of the component efficiencies, which are normally the turbine, drive system and generator. For a ‘typical’ small hydro system the turbine efficiency would be 85%, drive efficiency 95% and generator efficiency 93%, so the overall system efficiency would be 0.85 x 0.95 x 0.93 = 0.751 or 75.1%.

Therefore, if you had a relatively low gross head of 2.5 metres, and a turbine that could take a maximum flow rate of 3 m3/s, the maximum power output of the system would be:

First convert the gross head into the net head by multiplying it by 0.9, so Hnet = 2.5 x 0.9 = 2.25 metres.

Then convert the flow rate in m3/s into litres/second by multiplying it by 1000, so 3 m3/s = 3,000 litres/second. Remember that 1 litre of water weighs 1 kg, so ‘m’ is the same numerically as the flow rate in litres/second, in this case 3,000 kg/s.
Now you are ready to calculate the power:

    Power (W) = m x g x Hnet x System efficiency
    = 3,000 x 9.81 x 2.25 x 0.751
    = 49,729 Watts or 49.7 kW

Now, do the same for a high-head hydropower site where the gross head is 50 metres and maximum flow rate through the turbine 150 litres / second.

In this case Hnet = 50 x 0.9 = 45 metres and the flow rate in litres/second is 150, hence:

    Power (W) = m x g x Hnet x System efficiency
    = 150 x 9.81 x 45 x 0.751
    = 49,729 Watts or 49.7 kW

What is interesting here is that for two entirely different sites, one with a net head of 2.25 metres and the other 45 metres, can generate exactly the same amount of power because the low-head site has much more flow (3,000 litres / second) compared to the high-head site with just 150 litres/second.

This clearly shows how the two main variables when calculating power output from a hydropower system are the head and the flow, and the power output is proportional to the head multiplied by the flow.

Of course the two systems in the example above would be physically very different. The low head site would need a physically large Archimedean Screw or Kaplan turbine inside a turbine house the size of a large garage because it would have to be physically large to discharge such a large volume of water with a relatively low pressure (head) across it. The high-head site would only need a small Pelton or Turgo turbine the size of a fridge because it only has to discharge 5% of the flow rate of the low-head system and under a much higher pressure.

It is interesting that in the ‘real world’ the heads and flows in the example above aren’t too far from reality, because high-head sites tend to be at the heads of rivers in upland areas, so the ground slopes steeply enabling high heads to be created, but the rainfall catchment of the watercourse is relatively small, so the flow rate is small. That same upland stream 20 km downstream would have merged with countless small tributaries and formed into a much larger river with a higher flow rate, but the surrounding area would now be lowland agricultural land with only a modest gradient. It would only be possible to have a low head across a weir to avoid risking flooding the surrounding land, but the flow rate in the lowland river would be much larger to compensate.

The UK has a range of all types of high, medium and low head hydropower sites. England has more low-head sites, Scotland more high-head, and Wales a mixture of everything but still with significant medium and high-head opportunities.


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Microhydro Myths & Misconceptions

http://www.homepower.com/articles/microhydro-power/design-installation/microhydro-myths-misconceptions

Making electricity from falling water can seem like magic, and that’s led to lots of misconceptions. Here, we’ll separate fact from fiction when it comes to what microhydro systems can and cannot do.

Residential-scale microhydro-electric systems have the reputation of being the holy grail of home renewable-energy (RE) systems. While they lack some of the hype, magic, and bling of solar-electric (photovoltaic) systems, microhydro systems are a simple technology that most people can understand…at least in general. In this article, we’ll look at some common microhydro system misconceptions, most of which come from folks looking for shortcuts to the reward of cheap electricity.

Modern microhydro equipment comes from proven technology based on designs that have changed very little over the decades. Pelton and turgo wheels, the typical spinning water-wheel component, were invented in 1870 and 1919, respectively. The point is, this technology has proven its reliability and functionality with more than a century of performance.

The cost of these systems, and thus the cost of the resulting electricity, also has the reputation for being very reasonable when compared to other renewable or home-generated sources. While PV module prices have recently dropped, they are still a high-tech and expensive commodity. Microhydro systems can arguably be considered low-tech, with civil works and pipelines often being the majority of the system cost. Of course, the actual cost varies significantly from site to site, and from system to system.

Another element that keeps microhydro-generated electricity low in cost, and thus high in desirability, is the system’s continuous duty cycle. While PV systems only produce electricity when the sun is shining (and wind-electric systems when the wind is blowing), microhydro systems aren’t affected by nightfall or weather blocking the sun. Even a small hydro resource can provide electricity 24 hours a day, and often 365 days a year (if the water source is year-round). The bottom line for any renewable energy system is the amount of energy it can produce annually. A low power source working all of the time can often produce a lot more energy than a more powerful source that only works intermittently.

So, why doesn’t everyone have a microhydro system? Herein lies the challenge. A viable hydro resource is dependent on the availability of falling water at, or near, the site of the electrical loads. It is the weight or pressure of that flowing water that spins the turbine to produce electrical energy. Not everyone has access to a stream or spring of adequate volume on their property, nor does everyone have the topography to create the vertical drop needed to pressurize that water with gravity. See the “Microhydro Rules” sidebar for a formula about how water flow and vertical pressure (head) combine to determine the power available from a potential hydro site. That site-assessment formula will help debunk some of the myths that follow.

Many microhydro misconceptions are a combination of misunderstanding some of the basic properties of physics, and an overzealous optimism about the potential of RE resources. Here, we hope to correct the misconceptions about physics, while at the same time further encouraging educated optimism. Once you’ve had a little reality check here, we suggest you read some of Home Power’s other articles on the basics of hydro site assessment and microhydro systems (see Access at the end of this article). Perhaps you really do have untapped hydro potential waiting for you.

Myth 1: Closed-Loop / Pumped Storage

By far, the most common flawed design that we hear about at Home Power is the closed-loop system—that is, some scheme to pump water for the hydro turbine, and then have the turbine produce the electrical power for the pump…ad infinitum. Some of these schemes are simple “hydro-in-a-bucket” designs where the pump is expected to pressurize the water for the hydro turbine. Others are more involved, planning to pump water uphill to a pond or tank, and then let gravity do the job of running the turbine. All the while, the designer is expecting to get extra usable electric power from the turbine’s output—beyond what the pump is using. Whether large or small, all of these designs suffer from the same flaw in thinking.

The first law of thermodynamics says that energy can neither be created nor destroyed. All of the energy systems (renewable and otherwise) that we rely upon convert existing energy into a form that we can use to do the work we want to do. In a hydro-electric system, the energy of moving water is transferred to a rotating shaft, converted to changing magnetic fields, and then converted to moving electrons (electricity). But at no point is energy created. If we use that energy to create magnetic fields again, spinning a shaft and pumping water up to a tank on a hill, we still haven’t created any energy. We’ve just changed its form again.

In a perfect universe, perhaps it could be argued that such a pump and turbine arrangement could run perpetually. But it wouldn’t do us any good, because we want to use that electricity to do some work besides just running the pump. Using any electricity for other tasks would be robbing the pump of the power it needed to keep up with the turbine, and the loop’s interdependence would break down. That, and the fact that there are always other forces robbing energy from the system, means that such a loop wouldn’t run for long, and that no additional energy could be extracted from it.

Those additional energy-robbing forces, mostly friction, are the imperfections that cripple this closed-loop design. Every component of such a system has an operating efficiency of less than 100%. That means each conversion step in the process wastes some of the potential energy that the system started with. We know that energy is not being destroyed, but it is being allowed to escape the loop in the form of heat, vibration, and even noise. It is being converted into a form that we can’t readily use, or even recover.

Let’s look at some typical microhydro system efficiency numbers:

    Penstock (pipeline) efficiency = 95%
    Nozzle and runner efficiency = 80%
    Permanent-magnet alternator efficiency = 90%
    Wiring and control efficiency = 98%

0.95 × 0.80 × 0.90 × 0.98 = 0.67

By the time the water has moved through this example microhydro generator system, only 67% of its initial potential energy has been converted to electricity. In fact, this would be considered very good performance—typical systems are about 55% efficient.

Now let’s consider the efficiencies of pumping that water back to the hydro intake for reuse:

    Pipe efficiency = 95%
    Pump (motor and impeller) efficiency = 65%

0.95 × 0.65 × 0.67 (from above) = 0.41

By the time the water had gone all the way through the system, only 41% of it would be returned to the top of the intake. After a second loop around, only 17% (0.41 × 0.41) of the water would be left.

If there isn’t a water supply with useful head and flow to start with, nothing will happen—the pump won’t run because it won’t have electricity; the hydro turbine won’t have electricity because the pump isn’t running. Adding water (or electricity) to “prime” the loop will make the loop operate only as long as the priming continues.

This is where creative folks start asking questions about bigger water tanks; larger pipes with less friction loss; tanks on a tower for shorter pipe runs; more head, and less flow; less head and more flow; adding batteries (only 80% efficient themselves); or even just piping right from the pump to the turbine—anything to improve system efficiency. In fact, the simplest thing that could be done to get rid of inefficiencies would be to skip the water components altogether; just hook the shaft of a motor directly to the shaft of the alternator, and the alternators output wires directly to the motor (somehow, the fallacy in that thinking is easier for us to understand). But no matter the variables, the outcome will be the same—total efficiency will be less than 100% and no energy will be gained.

Moving energy around and changing its form, like from chemical to mechanical to electrical, is only a way to lose some of it. These efficiency losses are part of the price we pay to get energy into a format that we can use. We can lose more, or we can lose less, but adding complexity is inefficiency and will never result in a net gain.

Myth 2: Rooftop / Downspout Hydro

A second common microhydro-electric scheme that we are often asked about is the viability of putting turbines on a home’s gutter downspouts to generate electricity from the rain. Some imaginative folks know enough about hydro to understand that the energy has to come from somewhere (in this case, from the forces of nature), and that the height of the roof can contribute head (pressure) to spin that turbine.

The mistake in this scenario is a simple and honest one of scale. While some hydro units have been designed that can function on low head, such as from the roofline of typical homes (and even lower), a hydro turbine’s power output is a product of head times flow. And it is a lack of significant flow that is the defeating factor in the power equation when relying on rooftop rainwater collection. The watershed drainages for even small streams are usually measured in thousands of acres or square miles. Home roofs, even big ones, are measured in mere thousands of square feet.

Let’s look at example calculations for a large house in a very rainy place—Seattle, Washington, gets about 40 inches of rain per year, with November being the rainiest month at an average of about 6 inches.

Let’s assume that a tall two-story house would give us a 25-foot-high roof, and thus 25 feet of head. This 6,000-square-foot home has about 3,000 square feet of rainwater collection area (remember, it’s two stories). That means that in November, this house would receive about 1,500 cubic feet of rain, or 11,220 gallons.

If that rainfall came as a constant drizzle all month long, flow from the roof would be only about 1/4 gallon per minute. Currently there is no turbine on the market to work with that flows that low, but using our microhydro power formula (see sidebar), we could theoretically get 468 watt-hours that month.

0.26 gpm × 25 feet ÷ 10 derate = 0.65 watts × 720 hrs./mo. = 468 Wh

So even if there was a nanohydro plant that could harvest that small flow, it would result in less than 1/2 kWh of electricity—per month!—and only 3 cents worth of electricity in Seattle. It’s a tiny fraction of what even an energy-efficient, 6,000-square-foot home would use in a day, not to mention a whole month.

Would the available energy increase if we weren’t dealing with a constant drizzle? What if, to increase flows to a usable rate, and hopefully increase viable energy production, we could hope that all that rain came in a great deluge of 1 inch per hour (a 100-year storm, in Seattle) over six hours! At that unlikely amount of rain—practically all at once—flow from our example roof would be about 31 gpm. That is a more viable flow rate for hydro turbines on the market and gives us a projected power production of 77.5 watts, but only for those six hours. The total of 465 Wh per month is about the same energy as the drizzly example above (the minor difference is from rounding significant digits).

This is when inventive thinkers will begin planning for taller homes, or additional rain-collecting roof areas, and tanks to hold the water for release all at once to increase flow. But even that 11,220 gallons of water that falls on our 3,000-square-foot roof that month would weigh almost 47 tons if stored. Imagine a structure at roof level capable of supporting that kind of load just to generate a minuscule amount of energy. And remember, these discouraging energy production numbers are for the rainiest month, in one of America’s rainiest cities. Other months, other places, and smaller houses can only deliver worse performance.

In this case, it would be better to just spend the money on a PV system. To put things into perspective, even in Seattle, which gets only an average of 1.7 peak sun-hours per day in November, an inexpensive (less than $100) 15-watt PV module would make close to the same amount of energy as the proposed rooftop hydro system.

Myth 3: Hydro from Municipal Water Supply

So, a thinking person might begin wondering where they could get good water pressure and adequate flow necessary to run a microhydro turbine. It’s the kind of question an inspired hydro wannabe might ponder, say, while standing in the shower. And that’s when another common hydro scheme is hatched.

Typical municipal water pressure is between 40 and 80 psi, the equivalent of 92 to 185 feet of head. That is definitely enough for a hydro system. And if available flow is about 10 gallons per minute, say at the bathtub faucet, then surely there must be some real power available whenever we turn on our faucets.

However, if we use our example power formula with a common pressure of 60 psi (138 feet), we get a projected power output of about 138 watts.

138 ft. × 10 gpm ÷ 10 derate = 138 W × 24 hrs. = 3,312 Wh per day

That 3.3 kWh per day is something—but not a lot. An average American household uses about 30 kWh per day, so would need nine of these units.

For the sake of argument, let’s assume a very energy-efficient home that could run on 3.3 kWh per day. Why not then use such a hydro system? Or, why not offset a portion of a home’s loads with hydro? Every little bit helps, right?

The 3.3 kWh figure is based on using 10 gallons per minute—24 hours per day. That’s 14,400 gallons per day. At an average cost in the United States of $1.50 per 1,000 gallons, that’s $21.60 per day in water costs just to generate 36 cents worth of electricity (based on the U.S. average of $0.11 per kWh).

Then there is the ecological and moral impact—remember, this is water that has been treated and purified for human consumption, and uses pumps to maintain that pressure—processes likely paid for in part with taxpayer money. Costs aside, what are the implications of pouring good clean water down the drain just to make a little electricity?

Finally, just to add a final coup de grâce to this hydro scheme, remember that most of what we do with our domestic water requires water pressure, as well as flow, to get the job done. Taking the energy out of water to make electricity robs that water of its pressure—water merely falls dead (depleted of energy) out the bottom of a hydro turbine. And pressure at other faucets may be anemic at best—imagine trying to rinse shampoo out of your hair while a hydro system is running full-bore in the same home. Not so effective, or enjoyable.

Myth 4: Reducing Pipe Size to Increase Pressure / Power

There is no substitution for head and flow in an effective microhydro system. When head is inadequate, we begin to think of creative ways to increase pressure. The simple example of watering the garden with a hose comes to mind. Doesn’t putting your thumb partially over the hose opening increase the pressure, shooting water farther across the lawn? What if you use a spray nozzle instead of your thumb? Didn’t you just increase the power of that system by reducing the size of the nozzle? And therefore, couldn’t you increase head (and thus power) in a hydro system by starting off with a large pipe diameter and then reducing the pipe size on the way to the turbine?

Sorry, but no. When a pro measures head in a hydro system, they note two different types. Static head is the pressure at the turbine with the bottom valve closed, and thus no water moving. It is the pressure, from the weight of all the water in the pipe above the turbine. This pressure, measured in pounds per square inch (psi), is in direct proportion to the height of that column of water. For every 2.3 feet of vertical head, you’ll measure 1 psi. Because it is directly proportional, there’s no need to put in pipes and fill them with water to measure it; just measuring the vertical drop between water source and turbine site will give you an accurate static head.

But static head is just a maximum starting point. Dynamic head is the adjusted theoretical pressure in the system when inefficiencies like friction loss of pipes, joints, elbows, and valves are considered. These things hinder the flow of water through the system, and therefore some of its potential energy. Dynamic head is the result of static head minus these power losses, and provides a more accurate estimate of turbine performance.

Adding a smaller pipe section or nozzle is basically adding another restriction in the pipe that creates resistance to the flow of water. It effectively lowers the dynamic head of the system and thus also lowers the total power available in the system.

“Wait,” you say, “what about the hose spraying farther across the yard?” Or maybe you are savvy enough about hydro systems to know that impulse turbines actually use nozzles to shoot a stream of water at the spinning runner. Well, you are right, but neither pressure nor power are being increased by the nozzle. Instead, the existing energy is being concentrated into a smaller point and at higher velocity—which is a more usable form for the turbine—but, in the process, some of that energy is lost to friction.

The purpose of a nozzle is to increase the kinetic energy of the flowing water by increasing its velocity. But this is at the expense of its potential energy in the form of pressure. In fact, on the outlet side of a nozzle, there is no pressure in the water; it is carrying all of its energy in the form of fast-moving kinetic energy. And it is the force of this kinetic energy against the turbine’s runner that makes it spin. But no increase in energy was created. In fact, that water moving faster through a nozzle has more friction loss, reducing our dynamic head and total available power in the system—less power, but in a more useful form.

There is never any more power available than the theoretical maximum based on the initial static head (at a given flow). Every component and change in the form of energy in the system acts as an inefficiency, reducing actual available power. Some of those losses are necessary ones (getting the water down the hill, shooting it at the runner, etc.). Good design can reduce losses, but they can never be eliminated completely. And they definitely can’t be changed to net gains.

Myth 5: In-Flow / No-Head Systems

It’s starting to sound like only those folks with a stream or river on their property have a viable hydro system. But if you do have a good-flowing stream, you’re all set for hydro power, right? Well, it’s even more complicated than that.

We know that the power available to typical hydro turbines is a product of the head (pressure) and flow rate. So we also know that as head decreases, flow must increase to make the same amount of power. But what about folks with a nice river flowing along relatively flat ground? There must be some energy available in that strongly moving mass of water, even though it isn’t falling from a height, right? Well, yes and no.

Besides just turbine size, there are different turbine technologies designed to take advantage of the ratios of head-to-flow at a given hydro site. But as head decreases, the energy gets harder and harder to capture. Reaction turbines, designed for low heads (as low as 2 or 3 feet) spin inside a column of falling water, but need high flow for significant power.

But what about situations with basically no head at all? What about that big river flowing through a flat plain? Well, try putting zero head into our hydro power equation and you will find that, no matter how much flow there is, the power output will be zero, too. To be fair, there must be some head for the water in a stream to be moving at all, and thus there must be some power there to capture. But even though the movement of that flat-water stream looks enticing, there isn’t much potential to start with, compared to the same water dropping down a hillside. And then there’s the challenge in capturing it.

To make up for lack of head, flow would need to be substantial. Either the river must be flowing very fast, and/or a very large area of river must be captured. Both create challenges in the integrity of the mounting structure and turbine runner itself, plus the added danger from river debris.

A fast-moving river is often only moving fast in the center. Near the banks, shallows, or along the bottom, friction reduces the flow. The speed of the river in the center can’t necessarily be extrapolated to the whole cross-sectional area. Instead, there are specific formulas to account for the reduced flow along the bottom and shallow sides of a stream.

And even a quickly flowing river is moving a lot more slowly than the runner in a jet-driven impulse turbine in a system with higher head. A slowly spinning runner needs to be geared to create the rotational speeds necessary to generate electricity with an alternator. The gearing adds further complexity and friction loss to the system—more inefficiency.

We’re not saying that it can’t be done. But we are saying that it’s unlikely that you can buy anything off the shelf that will do an adequate job for you. There have been, and will continue to be, many inventions intended to capture energy from the flow in a river. These “in-flow” or “current turbine” designs come and go, and come again, but we rarely see anything that performs to a level that warrants a reliable consumer product. There are a couple of in-flow products on the market (Ampair and Jackrabbit) that were originally designed for towing behind sailboats or barges. Some have adapted these to use in streams, but the small swept area of their propeller requires high-velocity flow to make much usable power.

If you are a tinkerer, and enjoy the creative challenge of hydro design, you may be able to fashion an in-flow turbine to make some power (though it may never pay back financially). But if you are being tempted by commercially available in-flow turbine designs, caveat emptor. Do your homework by talking to other reputable hydro installers about your resource and options. Be realistic about your capturable stream area and flow rate. And ask for real-number data, and references, from the turbine manufacturer.

Head & Flow: Check Your Reality

While microhydro power is a reliable and proven technology, often at a reasonable cost, it’s completely dependent on the resources available on a site-by-site basis. Either your site has reasonable hydro potential, or it doesn’t. And it all depends on the quantities of head and flow. There’s no cheating the laws of physics. There is no way to create energy. There is no free lunch.

That doesn’t mean that there aren’t ways to optimize your hydro potential to get the most energy out of your resource. That’s where professional designers and reputable manufacturers come in. They have the knowledge to make decisions on siting and equipment that will maximize the energy made from the head and flow that is available. Intake type, pipe sizing and routing, the size and number of nozzles, runner type, alternator size and type, controller type, and system voltage are all variables that, when combined properly, will make or break your system performance and financial viability.

So give up on the free energy designs. Instead, read some of Home Power’s real-world articles on hydro system design, do a preliminary measurement of your stream’s actual head and flow, and call a reputable microhydro professional. That’s the best scheme for maximizing your hydro system’s performance.

Access

Benjamin Root is no expert on microhydro power, but with 15 years on staff with Home Power, he has seen a frustrating repetition of misconceptions about renewable energy’s potential…and hydro seems to take the brunt. Before you try to debunk Ben’s debunking, he suggests you do the same thorough research that he did to write this article.


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Myth 1: Closed-Loop / Pumped Storage
By far, the most common flawed design that we hear about at Home Power is the closed-loop system—that is, some scheme to pump water for the hydro turbine, and then have the turbine produce the electrical power for the pump…ad infinitum. Some of these schemes are simple “hydro-in-a-bucket” designs where the pump is expected to pressurize the water for the hydro turbine. Others are more involved, planning to pump water uphill to a pond or tank, and then let gravity do the job of running the turbine. All the while, the designer is expecting to get extra usable electric power from the turbine’s output—beyond what the pump is using. Whether large or small, all of these designs suffer from the same flaw in thinking.

hhop gen 3 uses a weight loaded ram (chamber b + piston) to energise liquid and therefore produce usable pressure. A 2% loss of liquid from an energised accumulator outlet nozzle will result in a total loss of fluid pressure. The ram must move to maintain fluid pressure and the energy to drive that ram is provided by gravity. The reason this works is because chamber b mass has been defined as a weight and therefore has a force vector only (downwards pressurising the piston onto the liquid and therefore energising it). If hydrostatic pressure equalisation of the liquid in chamber a and b was allowed to occur on the piston drive stroke (no seals), you lose pressure. The liquid in chamber b can still communicate hydraulically across the piston surface area to chamber a, but b is defined as a weight force only and it is unbalanced in the system at a higher gravitational potential. Chamber a is defined as a hydraulic scalar within the specific gravity field and therefore experiences hydrostatic pressure equalisation.

The first law of thermodynamics says that energy can neither be created nor destroyed. All of the energy systems (renewable and otherwise) that we rely upon convert existing energy into a form that we can use to do the work we want to do. In a hydro-electric system, the energy of moving water is transferred to a rotating shaft, converted to changing magnetic fields, and then converted to moving electrons (electricity). But at no point is energy created. If we use that energy to create magnetic fields again, spinning a shaft and pumping water up to a tank on a hill, we still haven’t created any energy. We’ve just changed its form again.

I accept these losses as entirely accurate for the systems discussed here, however hhop is a new type of pump that operates on gas pressure volume differential. The incoming liquid weight on the next pumping drive cycle (b) pumps the previous drive cycles liquid (a) back to the reservoir via the turbine and alternator to produce electricity. I am not using the electricity from the alternator to pump the water used to drive the turbine back up the hill to its original gravitational potential energy position (foot head psi). The hollow piston reset is the only process that requires a pump and a low energy high volume differential gas displacement pump can change the density of the piston and introduce a buoyancy force to the system that causes the piston to ascend.

In a perfect universe, perhaps it could be argued that such a pump and turbine arrangement could run perpetually. But it wouldn’t do us any good, because we want to use that electricity to do some work besides just running the pump. Using any electricity for other tasks would be robbing the pump of the power it needed to keep up with the turbine, and the loop’s interdependence would break down. That, and the fact that there are always other forces robbing energy from the system, means that such a loop wouldn’t run for long, and that no additional energy could be extracted from it.

hhop gen 3 gravity runs the pump, the electricity is used to reset the piston only. The ratio of electricity available at the turbine alternator output to the electricity required to displace the required volume of liquid from inside the hollow piston defines the coefficient of performance

Those additional energy-robbing forces, mostly friction, are the imperfections that cripple this closed-loop design. Every component of such a system has an operating efficiency of less than 100%. That means each conversion step in the process wastes some of the potential energy that the system started with. We know that energy is not being destroyed, but it is being allowed to escape the loop in the form of heat, vibration, and even noise. It is being converted into a form that we can’t readily use, or even recover.

hhop gen 3 works just the same, losses at every energy conversion stage. There are two cycles that the liquid will go through, b as a weight force vector and a as an unbalanced hydrodynamic flow seeking pressure equalisation (hence the jet of water out the bleed nipple to drive your turbine). Gravity is the input on each half cycle so the total system energy available is the total gravitational potential times two (b + b) minus losses times two, because the water at a has to get back to the reservoir at the turbine exhaust (starting gravitational potential before flowing in to b).   

Let’s look at some typical microhydro system efficiency numbers:

    Penstock (pipeline) efficiency = 95%
    Nozzle and runner efficiency = 80%
    Permanent-magnet alternator efficiency = 90%
    Wiring and control efficiency = 98%

0.95 × 0.80 × 0.90 × 0.98 = 0.67

By the time the water has moved through this example microhydro generator system, only 67% of its initial potential energy has been converted to electricity. In fact, this would be considered very good performance—typical systems are about 55% efficient.

Now let’s consider the efficiencies of pumping that water back to the hydro intake for reuse:

    Pipe efficiency = 95%
    Pump (motor and impeller) efficiency = 65%

0.95 × 0.65 × 0.67 (from above) = 0.41

By the time the water had gone all the way through the system, only 41% of it would be returned to the top of the intake. After a second loop around, only 17% (0.41 × 0.41) of the water would be left.

If there isn’t a water supply with useful head and flow to start with, nothing will happen—the pump won’t run because it won’t have electricity; the hydro turbine won’t have electricity because the pump isn’t running. Adding water (or electricity) to “prime” the loop will make the loop operate only as long as the priming continues.

This is where creative folks start asking questions about bigger water tanks; larger pipes with less friction loss; tanks on a tower for shorter pipe runs; more head, and less flow; less head and more flow; adding batteries (only 80% efficient themselves); or even just piping right from the pump to the turbine—anything to improve system efficiency. In fact, the simplest thing that could be done to get rid of inefficiencies would be to skip the water components altogether; just hook the shaft of a motor directly to the shaft of the alternator, and the alternators output wires directly to the motor (somehow, the fallacy in that thinking is easier for us to understand). But no matter the variables, the outcome will be the same—total efficiency will be less than 100% and no energy will be gained.

Moving energy around and changing its form, like from chemical to mechanical to electrical, is only a way to lose some of it. These efficiency losses are part of the price we pay to get energy into a format that we can use. We can lose more, or we can lose less, but adding complexity is inefficiency and will never result in a net gain.

Electrical energy required for system reset from the alternator output is directly related to gas volume in the displacement chamber inside the hollow piston. Change the run time on the alternator and you produce more electricity, if the piston diameter and volume remains constant you can increase liquid volume and therefore extend run time without effecting the ratio.


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What is Friction and What Does it Have to do with Rubber?
Written by Dale T. McGrosky

http://www.satoriseal.com/technical/technical_articles/what_is_friction.htm

How many times have you heard “What is an O-ring?” Without knowing it, O-rings are used in so many things in our daily lives and we just aren't aware of it. Friction is the same way. We rely on friction in our daily lives. For instance, friction is what keeps our tires glued to the road so your vehicle doesn't slide out of control. Tires without friction would be like driving on ice. I know, many of you are thinking “What about walking on ice?” It's the same thing, we rely on the friction between the soles of our shoes and the ground to keep us from slipping. By now I am sure the wheels are turning in your head and you're probably thinking of many other examples where the friction, or lack of friction, between two surfaces benefits us.

Friction is a force that opposes the movement of one object against another. There are three type of frictional forces, static, limiting and kinetic.

Static friction is the friction acting on and object when there is a force applied to the object while it is not moving. Lets explain this. Take an O-ring, or something that is not very slippery, and put it on a desktop. With your hand start to push on the o-ring in the direction you want it to slide without actually making it move. Now you are applying a force on the O-ring and it is not moving. Why? Because static friction is opposing the force you are applying to the O-ring. The frictional force is stronger than the force you are applying to the O-ring preventing it from sliding.

Limiting friction is the friction acting on an object just before it begins to move. This is often called breakout friction or its breakout point. Limiting friction is usually the highest friction, meaning, it usually takes more force to get something moving than to keep it moving. Lets explain this further. Ok, you should still have your hand on your O-ring and applying a force to it without making the o-ring move. Now, gradually increase the amount of force you are applying to the O-ring until it starts to move. Did you notice that once the o-ring started to move it required less force to keep it moving than it did to start it moving. Try it again but pay attention to the amount of force you are applying to the o-ring until it starts to move. The point just before the O-ring starts to move is called the limiting friction. It is were the frictional force is at its highest, usually.

Kinetic friction is the friction acting on an object while it is moving. To explain this one lets do a little comparison. You felt the frictional forces on the o-ring as you applied force to it while it was moving--right? Now, do the same thing to a piece of ice that you did with the O-ring. You will find that it takes less force to slide the ice across the desktop than the o-ring. This is because there is less kinetic friction between the ice and the desktop than the O-ring against the desktop. There is less frictional force opposing the ice moving on the desktop than the O-ring. Parents, this sounds like a pretty cool science fair project huh?

Friction is originated from electromagnetic forces and exchange forces between atoms and molecules. Electromagnetic forces and exchange forces (strong force) are two of the 4 fundamental forces, strong force, electromagnetic, weak force and gravity. Exchange force is any force that has to do with the exchange of particles. Technically all 4 forces can be classified as an exchange force.

Electromagnetic force is the force which holds the atoms together and keeps the electrons from flying off somewhere away from the atoms nucleus and also holds the atoms together to form molecules. You probably heard the phrase, “Like charges repel, opposite charges attract.” Two positive or two negative particles will repel while a positive and a negative particle will attract. Atoms are made up of neutrons (neutrally charged), protons (positively charges) and Electrons (negatively charged). The nucleus contains the protons and neutrons. The electrons travel around the nucleus in orbits similar to the planets in our solar system revolve around the sun. Neither the planets or electrons fly away because they are held in place by exchange forces. Electrons by the electromagnetic force and planets by gravity or gravitational force. It is the electromagnetic force that also keeps atoms together in molecules and causes an attraction or repulsion between two atoms.

Strong force (exchange force) is a fundamental force that acts on the nucleus of and atom. It is the force that binds particles together to form the neutrons and protons in the atom. The strong force is the strongest force. It can cause two protons to hold together despite the fact they are both positively charges and want to repel due to the electromagnetic force. The attraction of the strong force is stronger than the repulsion of the electromagnetic force.

So what do these forces have to do with friction? Certain molecules are going to attract to each other increasing frictional forces and some molecules repel reducing frictional forces. Lets look at what some call the most slippery material on earth – polytetrafluoroethylene (PTFE) or commonly referred to by its trade name Teflon®. PTFE is a long string of carbon atoms joined together with two fluorine atoms attached to each carbon atom. Fluorine, when attached to a molecule doesn't like any other molecule around it. It repels any other molecule even other molecules with fluorine atoms, hence its low coefficient of friction or slipperiness.

Coefficient of Friction

Lets say while you are sliding the O-ring across the desktop and you slide it through some grease left over from your french fries at lunch and suddenly the o-ring moves very easily with little force. You just modified the frictional coefficient or “Coefficient of Friction” with a lubricant. The same thing can be done to O-rings or rubber parts to reduce the coefficient of friction. 3 things can be done to reduce the coefficient of friction on rubber parts. You can coat the surface with a lubricant, add an internal lubricant to the compound, or modify the surface with fluorine, also called surface modification.

A lubricant can be applied to the surface of a rubber part to reduce the coefficient of friction. Some of the more common lubricants are silicone, molybdenum disulfide(MoS2), talc (baby powder), graphite, carnuba wax. These are temporary and do not stay on very long. They are primarily used to make installation easier. The surface can be coated with a polytetrafluoroethylene (PTFE or more commonly called Teflon®). PTFE coating is a thin layer of PTFE applied to the surface and them baked on in an oven. This is a little more permanent but can wear off or be scratched of the rubber. PTFE coating is not only used to reduce the coefficient of friction but the coatings are available in several colors which makes for great part identification on assembly lines. Another method of surface coating rubber is called chlorination. The rubber is introduced to chlorine gas which causes micro cracks on the surface which holds an external lubricant. This method is more permanent than PTFE coating.

Another method of lubricating rubber is to add a lubricant to the rubber compound as it is being mixed. The internal lube will slowly leach to the surface over time. This is great for dynamic applications where the rubber seal is moving during its use. Common internal lubricants are carnuba wax, PTFE, molybdenum disulfide (MoS2), graphite.

The newest method of reducing the coefficient of friction is “Surface Modification.” In this method the hydrogen atoms that are bonded with carbon atoms on the surface of the rubber are replaced with fluorine atoms. Remember fluorine above in the PTFE? When fluorine is bonded to a molecule it doesn't like other molecules -- It repels them making the molecule slippery. Also, fluorine is the most electronegative element. Electronegativity is the atoms ability to attract and share electrons with other molecules. What this means is once the fluorine atom bonds with the carbon atoms in the rubber molecule it doesn't easily come off making this process superior. The surface modified rubber can be used in dynamic applications where the O-ring moves and needs to maintain a low coefficient of friction surface that won't wear off.

Satori Seal can provide O-rings and seals with low coefficient of friction properties by any of the above methods.


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Low-friction seals lead to high machine efficiency

A novel hydraulic seal minimizes friction and leakage across a wide pressure range.

By Walter Igers
Thomas Papatheodorou
Parker Hannifin GmbH


http://hydraulicspneumatics.com/200/TechZone/Seals/Article/False/86292/TechZone-Seals

Cutting seal friction saves energy and helps eliminate undesirable stick-slip motion.

Operators of fluid-power systems increasingly demand friction-optimized piston and rod seals for hydraulic cylinders. Excessive friction not only wastes energy, it can also accelerate wear and lead to premature seal failure. But too little friction and a seal leaks. Getting the balance just right across varying pressures and operating conditions has been an ongoing challenge for seal manufacturers.

Parker Hannifin’s Seal Group has developed a product that meets this goal. The company’s new Ultrathan HL rod seal features a series of cascading, pressure-activated sealing lips that, according to Parker officials, reduce static and dynamic friction in hydraulic cylinders.

Compared with conventional U-rings, the HL single-acting rod seals reportedly reduce friction-related losses by 30 to 70%, depending on load, without compromising sealing capability. This increases hydraulic-system efficiency and can lead to significant energy savings.

Stepped pressure activation

Various parameters influence friction in hydraulic seals. The size of the contact area between the seal and respective sliding surface is one key factor. In essence, the larger the contact area, the higher the static and dynamic friction.

Also, hydraulic-system pressure dictates the amount of friction required to prevent fluid from leaking past the seal. For example, friction at lower system pressures, or in differential cylinders with small pressure differences, is significantly more critical than in cylinders operating at higher pressures. With conventional U-seals, a large portion of the dynamic sealing area typically contacts the piston-rod surface even at low system pressures, which increases friction. The HL takes a different approach.

The HL seal profile features three individual sealing lips that consecutively contact the mating surface as pressure rises. In low pressure or pressureless conditions only one lip contacts the rod. The resulting small contact area produces significantly less friction, compared with standard U-cups. And less friction means the seal generates less heat, permitting higher travel speeds. In addition, because only the primary sealing lip engages at low pressures, the HL minimizes breakaway friction typical after prolonged down time.

As system pressure rises, the seal’s cross section deforms slightly and additional sealing lips are activated. Thus, sealing capabilities increase with pressure and the number of sealing edges in contact with the rod.

Multiple sealing lips also reduce the amount of oil on the rod surface that seeps past the seal as the cylinder strokes, further reducing leakage. Although dynamic friction slightly increases as more lips engage and the contact area enlarges, overall, it remains at a low level. In addition, the design virtually eliminates the risk of stick-slip at slow travel speeds.

Pressure-activated sealing

The HL seal geometry features three sealing lips that consecutively contact the rod surface as pressure increases.

The result is low friction and tight sealing at all pressures.

New materials

Performance of the new geometry also depends on the seal material, a newly developed polyurethane called P6030.The material is specifically designed for low-friction, fluid-power applications. It handles a wide range of temperatures and has good mechanical strength, high extrusion and wear resistance, and low compression set. It is compatible with mineral-oil and PAO-based hydraulic fluids, and materials for bio fluids (HEES and HETG) are available as well.

Endurance tests performed according to ISO 7986 gauged the long-term performance of HL seals made of P6030. Seals were installed in cylinders with 36-mm diameter, hard-chrome-plated rods and a 250-mm stroke. The seals were subject to pressures from 0 to 200 bar, temperatures of 65°C, and rod speeds of 0.15 m/sec for 500 km (1 million cycles) to determine friction and leakage behavior as well as deformation and wear.

Results showed no significant extrusion, no abrasion on the sealing edge and surface, no changes in sealing edge contours, low plastic deformation of the seal profile, and low preloading loss (less than 30%).

Wide application range

The HL rod seal can be used as both a single seal with a wiper and in a sealing system — as a secondary seal behind a primary or buffer seal. The seals are designed for maximum operating pressures of 250 bar (3675 psi) and operating temperatures between –35° and 110°C.

The HL Ultrathan rod seal is suitable for a wide range of hydraulic applications requiring minimal friction, such as lifting platforms, lift trucks, and loading gates. Test and automation cylinders, cylinders for ag equipment, and gas springs are other typical applications.

Walter Igers is Development Engineer and Thomas Papatheodorou is Manager of Technical Services at Parker Hannifin GmbH, Packing Div., Europe, Bietigheim-Bissingen, Germany. For more information, contact the Parker Hannifin Seal Group, Cleveland, or visit www.parker.com.

Friction-force tests

Parker engineers performed a series of tests to compare the behavior of the HL design with that of other commonly used seals. Friction-force tests were conducted at varying pressures, temperatures, and speeds on both new seals and seals previously subjected to prolonged endurance tests.

Friction and pressure

Test show that compared with standard U-seals and other friction-modified seals, the HL seal reduces friction across a wide pressure range.

Speed tests

The HL geometry helps eliminate stick-slip conditions at low speeds.

Results revealed that the HL seal geometry clearly reduces friction, compared with conventional U-seals and other versions of friction-modified seals. This applies across a wide pressure range from low levels up to 200 bar.

At low speeds the new design exhibits significant friction benefits. Particularly with regard to undesirable stick-slip, improvements were seen at higher temperatures and speeds across the entire pressure range.

The comparison demonstrates that friction losses encountered with the HL rod seal, depending on the load, can be reduced by 30 to 70% compared with a standard U-seal. This results in considerable energy savings, benefiting operating budgets and the environment.


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Vector field

In vector calculus, a vector field is an assignment of a vector to each point in a subset of space.[1] A vector field in the plane, for instance, can be visualized as a collection of arrows with a given magnitude and direction each attached to a point in the plane. Vector fields are often used to model, for example, the speed and direction of a moving fluid throughout space, or the strength and direction of some force, such as the magnetic or gravitational force, as it changes from point to point.

The elements of differential and integral calculus extend to vector fields in a natural way. When a vector field represents force, the line integral of a vector field represents the work done by a force moving along a path, and under this interpretation conservation of energy is exhibited as a special case of the fundamental theorem of calculus. Vector fields can usefully be thought of as representing the velocity of a moving flow in space, and this physical intuition leads to notions such as the divergence (which represents the rate of change of volume of a flow) and curl (which represents the rotation of a flow).

In coordinates, a vector field on a domain in n-dimensional Euclidean space can be represented as a vector-valued function that associates an n-tuple of real numbers to each point of the domain. This representation of a vector field depends on the coordinate system, and there is a well-defined transformation law in passing from one coordinate system to the other. Vector fields are often discussed on open subsets of Euclidean space, but also make sense on other subsets such as surfaces, where they associate an arrow tangent to the surface at each point (a tangent vector).

More generally, vector fields are defined on differentiable manifolds, which are spaces that look like Euclidean space on small scales, but may have more complicated structure on larger scales. In this setting, a vector field gives a tangent vector at each point of the manifold (that is, a section of the tangent bundle to the manifold). Vector fields are one kind of tensor field.

https://en.wikipedia.org/wiki/Vector_field

Raised Weight Accumulator

A raised weight accumulator consists of a vertical cylinder containing fluid connected to the hydraulic line. The cylinder is closed by a piston on which a series of weights are placed that exert a downward force on the piston and thereby energizes the fluid in the cylinder. In contrast to compressed gas and spring accumulators, this type delivers a nearly constant pressure, regardless of the volume of fluid in the cylinder, until it is empty. (The pressure will decline somewhat as the cylinder is emptied due to the decline in weight of the remaining fluid.)

https://en.wikipedia.org/wiki/Hydraulic_accumulator#Raised_weight

Hydrostatic Equilibrium

In continuum mechanics, a fluid is said to be in hydrostatic equilibrium or hydrostatic balance when it is at rest, or when the flow velocity at each point is constant over time. This occurs when external forces such as gravity are balanced by a pressure gradient force.[1] For instance, the pressure-gradient force prevents gravity from collapsing Earth's atmosphere into a thin, dense shell, whereas gravity prevents the pressure gradient force from diffusing the atmosphere into space.

Hydrostatic equilibrium is the current distinguishing criterion between dwarf planets and small Solar System bodies, and has other roles in astrophysics and planetary geology. This qualification typically means that the object is symmetrically rounded into a spheroid or ellipsoid shape, where any irregular surface features are due to a relatively thin solid crust. There are 31 observationally confirmed such objects (apart from the Sun), sometimes called planemos,[2] in the Solar System, seven more[3] that are virtually certain, and a hundred or so more that are likely.[3]

https://en.wikipedia.org/wiki/Hydrostatic_equilibrium

The hhop gen 3 piston isolates the two hydrostatic liquid chambers, thus ensuring that the upper chamber has only a gravitational vector force acting upon the system, the scalar specific gravity field hydrostatic pressure is equalised internally within the container walls and open to atmospheric pressure. This creates a raised weight accumulator system to drive an alternator and pump the lower chamber water back to the reservoir at turbine exhaust. Looping this system would always be COP<1 (less than 1)due to the losses incurred on each cycle.

For a given flow rate the Pelton turbine will produce a constant electrical output. Electrolysis allows us to create a phase change in the lower water chamber, below the piston, causing a large stable volume pressure differential.. and pumping water. The heavy dense water has been replaced with a light low density gas and therefore a buoyancy effect has been introduced to the system. This creates a lifting force on the piston that must exceed breakout friction of the seals and the weight of the piston itself to raise it within the liquid column.

The energy available at the alternator output is now directly related to the energy required to create the gas from the electrolysis process. All steps in this process are less than 100% efficient as they are operating within a single frame or reference, the gravitational vector field which acts on everything with a relative downwards force (the force trying to pull you down through your chair right now).

However, the force required from buoyancy to raise the piston can be quantified and experimentally validated, becoming a constant for that system. The volume of the hollow piston will be fixed, its diameter and its height are fixed, therefore the diameter of the system liquid column is fixed.. but the height of both water chambers becomes a variable and equal to each other (as they are equal in size). The height of the water reservoirs is a variable in the first frame of reference, the gravitational vector field.. the piston is a constant in the second frame of reference, the specific scalar gravity field.. as a result all the work required to lift the piston weight through a vertical height is supplied by gravity in the first frame of reference vector field.. the process to access the secondary specific gravity field is accomplished from the phase change of liquid to gas and exploiting the volume pressure spring compression differential.


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Archimedes' principle

https://en.wikipedia.org/wiki/Archimedes%27_principle

Archimedes' principle is named after Archimedes of Syracuse, who first discovered this law in 212 B.C.[4] For objects, floating and sunken, and in gases as well as liquids (i.e. a fluid), Archimedes' principle may be stated thus in terms of forces:

"Any object, wholly or partially immersed in a fluid, is buoyed up by a force equal to the weight of the fluid displaced by the object."

— Archimedes of Syracuse


 8)

Add an electromagnet to your hhop electrolysis cell and trigger shock to your piston ring magnet, when your piston is at bottom of travel, and overcome breakout friction therefore reducing electrical energy required to balance gas creation demand (alternator to hho cell relationship). Volume of gas displacement required is potentially reduced and therefore electrical energy requirement from the alternator (run time from volume and energise pressure of top water chamber).

http://www.onlineconversion.com/object_volume_cylinder_tank.htm

http://www.onlineconversion.com/object_volume_cylinder.htm



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Height

https://en.wikipedia.org/wiki/Height

Height is the measurement of vertical distance, but has two meanings in common use. It can either indicate how "tall" something is, or how "high up" it is. For example "The height of the building is 50 m" or "The height of the airplane is 10,000 m". When used to describe how high something like an airplane or mountain peak is from sea level, height is more often called altitude.[1] Height is measured along the vertical (y) axis between a specified point and another point.

In mathematics

In elementary models of space, height may indicate the third dimension, the other two being length and width. Height is normal to the plane formed by the length and width.

What have i done to the height dimension of the liquid cylinder chamber 'a' and 'b'.. input and output.. of the hhop gen 3 system, how is the hollow piston involved. ? how are they related in both frames of reference.. vector gravitational field and scalar specific gravity field.. from the latter COP>1 energy can be extracted.. as a user defined variable..!


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On the Sphere and Cylinder

https://en.wikipedia.org/wiki/On_the_Sphere_and_Cylinder?searchDepth=1

On the Sphere and Cylinder (Greek: Περὶ σφαίρας καὶ κυλίνδρου) is a work that was published by Archimedes in two volumes c. 225 BC.[1] It most notably details how to find the surface area of a sphere and the volume of the contained ball and the analogous values for a cylinder, and was the first to do so.[2]

and that the volume of the same is:

Volume = pi times the radius squared times the Height.

https://en.wikipedia.org/wiki/Pi


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Newton's law of universal gravitation

https://en.wikipedia.org/wiki/Newton's_law_of_universal_gravitation

Newton's law of universal gravitation states that any two bodies in the universe attract each other with a force that is directly proportional to the product of their masses and inversely proportional to the square of the distance between them.[note 1] This is a general physical law derived from empirical observations by what Isaac Newton called induction.[2] It is a part of classical mechanics and was formulated in Newton's work Philosophiæ Naturalis Principia Mathematica ("the Principia"), first published on 5 July 1687. (When Newton's book was presented in 1686 to the Royal Society, Robert Hooke made a claim that Newton had obtained the inverse square law from him; see the History section below.)

In modern language, the law states: Every point mass attracts every single other point mass by a force pointing along the line intersecting both points. The force is proportional to the product of the two masses and inversely proportional to the square of the distance between them.[3] The first test of Newton's theory of gravitation between masses in the laboratory was the Cavendish experiment conducted by the British scientist Henry Cavendish in 1798.[4] It took place 111 years after the publication of Newton's Principia and 71 years after his death.

Newton's law of gravitation resembles Coulomb's law of electrical forces, which is used to calculate the magnitude of electrical force arising between two charged bodies. Both are inverse-square laws, where force is inversely proportional to the square of the distance between the bodies. Coulomb's law has the product of two charges in place of the product of the masses, and the electrostatic constant in place of the gravitational constant.

Newton's law has since been superseded by Einstein's theory of general relativity, but it continues to be used as an excellent approximation of the effects of gravity in most applications. Relativity is required only when there is a need for extreme precision, or when dealing with very strong gravitational fields, such as those found near extremely massive and dense objects, or at very close distances (such as Mercury's orbit around the sun).

Vector fields on spheres

https://en.wikipedia.org/wiki/Vector_fields_on_spheres

In mathematics, the discussion of vector fields on spheres was a classical problem of differential topology, beginning with the hairy ball theorem, and early work on the classification of division algebras.

Differential topology

https://en.wikipedia.org/wiki/Differential_topology

In mathematics, differential topology is the field dealing with differentiable functions on differentiable manifolds. It is closely related to differential geometry and together they make up the geometric theory of differentiable manifolds.

Differentiable manifold

https://en.wikipedia.org/wiki/Differentiable_manifold

In mathematics, a differentiable manifold is a type of manifold that is locally similar enough to a linear space to allow one to do calculus. Any manifold can be described by a collection of charts, also known as an atlas. One may then apply ideas from calculus while working within the individual charts, since each chart lies within a linear space to which the usual rules of calculus apply. If the charts are suitably compatible (namely, the transition from one chart to another is differentiable), then computations done in one chart are valid in any other differentiable chart.

In formal terms, a differentiable manifold is a topological manifold with a globally defined differential structure. Any topological manifold can be given a differential structure locally by using the homeomorphisms in its atlas and the standard differential structure on a linear space. To induce a global differential structure on the local coordinate systems induced by the homeomorphisms, their composition on chart intersections in the atlas must be differentiable functions on the corresponding linear space. In other words, where the domains of charts overlap, the coordinates defined by each chart are required to be differentiable with respect to the coordinates defined by every chart in the atlas. The maps that relate the coordinates defined by the various charts to one another are called transition maps.

Differentiability means different things in different contexts including: continuously differentiable, k times differentiable, smooth, and holomorphic. Furthermore, the ability to induce such a differential structure on an abstract space allows one to extend the definition of differentiability to spaces without global coordinate systems. A differential structure allows one to define the globally differentiable tangent space, differentiable functions, and differentiable tensor and vector fields. Differentiable manifolds are very important in physics. Special kinds of differentiable manifolds form the basis for physical theories such as classical mechanics, general relativity, and Yang–Mills theory. It is possible to develop a calculus for differentiable manifolds. This leads to such mathematical machinery as the exterior calculus. The study of calculus on differentiable manifolds is known as differential geometry.


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Differential geometry

https://en.wikipedia.org/wiki/Differential_geometry

Differential geometry is a mathematical discipline that uses the techniques of differential calculus, integral calculus, linear algebra and multilinear algebra to study problems in geometry. The theory of plane and space curves and surfaces in the three-dimensional Euclidean space formed the basis for development of differential geometry during the 18th century and the 19th century.

Since the late 19th century, differential geometry has grown into a field concerned more generally with the geometric structures on differentiable manifolds. Differential geometry is closely related to differential topology and the geometric aspects of the theory of differential equations. The differential geometry of surfaces captures many of the key ideas and techniques characteristic of this field.


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Everyman Standing Order 01: In the Face of Tyranny; Everybody Stands, Nobody Runs.
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I was chatting to Graham earlier and I mentioned I don't mind if he makes his hhop gen 2 prototype video available to the general public:

https://www.youtube.com/watch?v=rqBq5aTvCOE

Listen to what Graham says between 2:40 and 2:48..

"I don't know whether Rob's thought was to.. it's actually moving the water prior to it being.. zzzzzz.. heh!"

In that moment Graham realised there are two cycles within the hhop process doing work, the gas displacement cycle and the combustion cycle. Those of you that understand hhop gen 3 will know that the two cycles are separated and the unused hho ignition recombination phase transition event energy release is available to be added to system output energy without being involved in the system ratio balance!


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Everyman Standing Order 01: In the Face of Tyranny; Everybody Stands, Nobody Runs.
Everyman Standing Order 02: Everyman is Responsible for Energy and Security.
Everyman Standing Order 03: Everyman knows Timing is Critical in any Movement.
   

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Posts: 2502
Everyman decries immorality
I was chatting to Graham earlier and I mentioned I don't mind if he makes his hhop gen 2 prototype video available to the general public:

https://www.youtube.com/watch?v=rqBq5aTvCOE

Listen to what Graham says between 2:40 and 2:48..

"I don't know whether Rob's thought was to.. it's actually moving the water prior to it being.. zzzzzz.. heh!"

At 2:48 - 2:49 in the video the spark gap fires and the pipe jumps. Logic tells us that the ignition sent (what appears to us as instantaneous) a shockwave and made the pipe jump about. The water you can see pumped in spurts into the receiver later in the video is a secondary effect created by a reciprocal oscillating linear fluid mass (in this case highly dense liquid).


---------------------------
Everyman Standing Order 01: In the Face of Tyranny; Everybody Stands, Nobody Runs.
Everyman Standing Order 02: Everyman is Responsible for Energy and Security.
Everyman Standing Order 03: Everyman knows Timing is Critical in any Movement.
   

Group: Moderator
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Everyman decries immorality
hhop gen 2 Hybrid

Uses atmospheric pressure equalisation to bleed the chamber of a less dense gas.

As a result a reservoir sump can be dug into any stream bed, even a shallow slow running stream, and hhop can be placed below the water line requiring no combustion cycle to function.

 8)


---------------------------
Everyman Standing Order 01: In the Face of Tyranny; Everybody Stands, Nobody Runs.
Everyman Standing Order 02: Everyman is Responsible for Energy and Security.
Everyman Standing Order 03: Everyman knows Timing is Critical in any Movement.
   
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