About a two weeks go, two guys successfully were able to convert gasoline powered generator engine to run with a refrigerant fluid/gas.
This was done in a fully looped closed system. After initial start up, generator was totally self powered and was able to run 3 times more
load that generator was designed power it so. Probably a short period of time, or else generator would burn up a fuse etc.
Another guy "Bill" who knows these two guys wrote this pdf file.
Seems good and clear instructions and part numbers and all that but there is no drawings or pictures yet. To what is worth, I am sharing with you.
Mehmet
Is this "Alaska star" Chris Hunter??
must be, it has been a quite a few years since I last spoke with Chris
a truly wonderful and gifted young man .........
think I'll give him a ring when I get back home next week.
thx for sharing this ,
Chet K
Hi Chet, I think so, but never spoke to him myself. But I know the Bill that he is touch with him (two them). Hopefully some one can make a simple drawing to ad to these instructions. Nice to have a drawing that goes with it. Apparently there is somebody else that started to test this idea, you can the read the rest here. http://cr4.globalspec.com/thread/84740/Refrigerant-for-engine-power-not-freon-for-Solar-generator (http://cr4.globalspec.com/thread/84740/Refrigerant-for-engine-power-not-freon-for-Solar-generator) .
Years a go the "Famous Dennis Lee" proclaimed that they create a similar generator that draw the power from environment. He called "Fisher Engine" you can see that engine picture here http://www.abodia.com/f/Images/Dennis1.gif (http://www.abodia.com/f/Images/Dennis1.gif)
Mehmet.
l'd think there will be some piston blow by, allowing the working gas to bleed into the crankcase. The crankcase will have to be sealed or the working fluid will be lost. This means probably having to seal off the PCV orifice and maybe even add some positive pressure to the crankcase.
I am very glad to see that Alaska Star has apparently
succeeded in his effort to make such an engine. He
began work on it several years ago and kind of "disappeared"
from the forums.
Mrgalleria has done a lot of work with electrolyzers.
Good to see that the two of them have teamed up on
this project.
Chet
Here is that video i was talking about. Not to sure about this guy?.
https://www.youtube.com/watch?v=Yt_hqmgwMBU
Quote from: ION on 2014.05.12, 01:33:50
l'd think there will be some piston blow by, allowing the working gas to bleed into the crankcase. The crankcase will have to be sealed or the working fluid will be lost. This means probably having to seal off the PCV orifice and maybe even add some positive pressure to the crankcase.
Hi ION
You dont want a positive pressure in the crank case,as this will act against the piston when it is in the power and inlet stroke.The simple fix is to let the PCV valve do it's job,and that is to relieve crank case pressure.In almost every engine(4 stroke) the crank case pressure go's through the PCV valve,and directly back into the inlet,via the air filter. The ICE is not the ideal engine design for this setup.You would be far better using a diaphragm based engine for this kind of system.
https://www.youtube.com/watch?v=Ljb7R09f-8k
Quote from: TinMan on 2014.05.12, 13:14:34
Hi ION
You dont want a positive pressure in the crank case,as this will act against the piston when it is in the power and inlet stroke.The simple fix is to let the PCV valve do it's job,and that is to relieve crank case pressure.In almost every engine(4 stroke) the crank case pressure go's through the PCV valve,and directly back into the inlet,via the air filter. The ICE is not the ideal engine design for this setup.You would be far better using a diaphragm based engine for this kind of system.
https://www.youtube.com/watch?v=Ljb7R09f-8k
While your statement is true for a single cylinder engine, it is untrue for any even number of cylinders, as when one is going up another goes down, the pressure evens out. That is what I was referring to.
A diaphragm pump would definitely be a better choice. Heat pumps are generally sealed systems so careful attention must be paid to shaft seals, dipsticks etc. if one is trying to convert an ICE to a heat pump or heat motor.
Piston blow-by is real.
Quote from: ION on 2014.05.12, 14:45:47
While your statement is true for a single cylinder engine, it is untrue for any even number of cylinders, as when one is going up another goes down, the pressure evens out. That is what I was referring to.
A diaphragm pump would definitely be a better choice. Heat pumps are generally sealed systems so careful attention must be paid to shaft seals, dipsticks etc. if one is trying to convert an ICE to a heat pump or heat motor.
Piston blow-by is real.
Ion, I agree with diaphragm pump idea, it's a very good choice. But what would you do with diaphragm pump? Circulate fluid to power hydraulic motor? How about air motor, would it not work?
Dear All.
Chet phoned me, all excited !! I have read the PDF about 3 times over, well the relevant bit's anyway and I have one pertinent question.
The process seems simplicity in itself but?? Let us take a simple 100 cc Petrol / Gasoline side valve engine, perhaps from a Lawnmower. Compression pressure would reach just over 100 PSI (7Bar approx.) The suggested injector is designed to inject into the inlet manifold not directly into the cylinder. Motorcraft are rating their injector for a maximum gas pressure of 4 Bar. We immediately have a problem that when the injector is opened the gas will see 7 bar of pressure in the cylinder versus 4 Bar on the injection line !! It aint goin to work !! :)
Apart from that one single problem the working principle seem sound. So I think we need to find a suitable direct injector with a delivery pressure greater than the compression pressure. All other worries like piston "blow by" can be easily dealt with by the use of a suitably placed NRV and returned into the low pressure side for reuse.
Thoughts ??
Cheers Grum.
http://en.wikipedia.org/wiki/Common_rail
QuoteThird-generation common rail diesels now feature piezoelectric injectors for increased precision, with fuel pressures up to 3,000 bar (300 MPa; 44,000 psi).[1][2]
Quote from: Peterae on 2014.05.12, 20:22:59
http://en.wikipedia.org/wiki/Common_rail
Dear Peterae.
I am quite familiar with the common rail Diesel engine injector and yes a great idea. But we only need, say 10 bar max !! I wonder whether the maximum ratings for the LPG injector could be exceeded ? I have had very little to do with Refrigeration equipment. How much pressure can be generated by a small Vehicle Air Con system ??
I am quite seriously interested in this one !! I have several Donor Suffolk Colt lawnmower engines to play with and I am also, luckily enough, to have a friend who's business is LPG conversions and also does Aircon repairs. Ace in the hole !! O0 I will ring him tomorrow and ask some questions. And I hope get some answerers that I can share with us all?
Cheers Grum.
Grum
I will try to get in contact with Chris again
This is a project he was building last we spoke.
http://peswiki.com/index.php/Directory:ArcticTek:Chris_Hunter_(Alaska_Star)'s_Axial_Flux_Motor
Yes this is very intriguing .
I also started a topic here [some interest here]
http://www.energeticforum.com/renewable-energy/17019-chris-hunter-alaska-star-releases-o-u-pdf.html#post255631
Chet
Hi Grum
Here's some info about air con pump pressures
https://uk.answers.yahoo.com/question/index?qid=20060718155308AAjfrPU
I will keep quiet now as i am sure you know a lot more than me on this subject, is interesting anyway O0
more to come.........
I am corresponding with Chris
I have invited him to assist.
Will keep you posted.
thx
Chet
Many say a sealed system turbine is the way to go for recovering waste heat.
Here is a company that has 5 models in production.
http://www.infinityturbine.com/ORC/ORC_Waste_Heat_Turbine.html
I explored the patents on this and other designs and find they go way back to the 1930's
Rather than try to retrofit / modify an ICE with all of it's problems, piston type refrigeration compressors might make more sense.
;D
Love this...
On the Horizon is PRotoMax, AHELNI, PHELIS, HRT and other integratable technologies.
Cannot wait!
O0
http://www.overunity.com/10347/ahelni-advanced-hydro-electro-lytic-nozzle-insert/#.U3JPxCiUMYE
Quote from: Chet K on 2014.05.13, 11:17:09
more to come.........
I am corresponding with Chris
I have invited him to assist.
Will keep you posted.
thx
Chet
Dear Chet.
Many thanks, but is it really this simple ??
Cheers Grum
Grum
Pretty Much,
and I have verification from Chris that it works "GREAT"as outlined in the PDF....
for the sake of a better replication I will see if a Pic can be shared?
thx
Chet
Using this below but recycling the CO2 you have what is proposed O0
http://www.infinityturbine.com/ORC/New_-_Supercritical_CO2_System.html
regards
Mike
PS.
Their heat exchanger could be a lot better, my patented system would be up to 20% better. >:-)
Actually it can be very simple, just one moving part, turbine and pump running on the same shaft in a totally sealed system with a hot end (evaporator) and cold end (condenser). See attached.
A long time ago,I came up with a design that inverts the turbine and pump shown in the drawing, at opposite ends of the sealed container and circulates the working fluid through the hollow connecting shaft.
Nice ION, I like things simple O0
But to get a prototype built from parts easily got hold of I would suggest a turbo charger from a car engine might be adapted as the turbine, they are designed just as we want, to work off expansion of gases
http://en.wikipedia.org/wiki/Turbocharger
I designed one to work on H2 and N2 many years ago ;) This one built by Aaron of EF under my plans and direction just for that purpose :D
regards
Mike
Dear All.
A bit of history. As there is nothing new !! Old ideas in new clothes !!
See attached from 1873. Patent granted 1868.
I have a 1/3 rd scale partially built model of this.
Cheers Grum.
Graham
good stuff
there are a few other places where this thread will be "mirrored"
http://www.energeticforum.com/renewable-energy/17019-chris-hunter-alaska-star-releases-o-u-pdf.html#post255715
and here
http://www.overunity.com/14628/chris-hunter-alaska-star-releases-an-o-u-pdf/msg402360/#new
For clarity Graham will be replicating Chris Hunter's [AlaskaStar] work with the intention of a public showing in the UK next month.
For additional Clarity My use of the "OU" term in those threads is a bit "Hollywood" but has roots in Perspective....[looped closed system].
old habits die hard!!
thx
Chet
Dear All.
I have thought of a simple possible method of overcoming the cylinder pressure. We could close couple a "Mainline" gas solenoid valve (these are designed to shut off the gas from the supply tank on LPG vehicles) to an Oil fired boiler spray nozzle !! This idea might just work in providing an atomised spray of liquid refrigerant into the cylinder.
I have just finished in conversation with Chet and He is convinced we need two cylinders for this engine to work? I on the other hand think that a "Decent" flywheel should do the trick. Think about it for a moment. We are just using a material that expands within the cylinder !! Identical to igniting a fuel air mixture. That works singly, doesn't it ??
Cheers Grum.
Grum
Your intuition makes sense,My comment was based on the PDF's direction .
Good stuff happening here!
thx
Chet
I have been giving this some thought,and think i have a cheap way to convert a standard gas engine to do what you want it to do.The biggest problem is like ION mentioned-blow by. If we take a standard single cylinder engine(e.g,honda,chonda,robbin,etc),there would be enough meat on the piston to remove the standard piston ring's,and machine one of the piston ring grooves to take a hydraulic ram seal. The cylinder can then be polished using a buffer disk of right diameter,and cutting compound- used to cut and polish car paint.This will give the cylinder a mirror finish to ensure a perfect seal.These seal's will handle a quite high temp,and i dont think this type of setup would generate much heat at all within the engine-in fact, i think there would be freezing problem's insted.
My question about this setup working is-how do you recompress the gas back to a liquid state?,as it will take as much energy to do that,as what the expanding gas would give off.
Quote from: TinMan on 2014.05.16, 13:43:11
My question about this setup working is-how do you recompress the gas back to a liquid state?,as it will take as much energy to do that,as what the expanding gas would give off.
Your excess energy comes from a heat source (ambient) @ around 3:1 worst case or 5:1 with scroll compressors, you will have what you need to drive a generator. Should be no problem where you are Brad, just put a nice big radiator in the sun and pump the normally cooling water around the engine. The other thing is the liquid/gas phase change, the liquid is injected at TDC and the flywheel pulls a vacuum with the piston as it goes down, liquid then changes instantly to gas creating expansion. There is a big volume difference between liquid and gas phase, this is where your power comes from.
The best AC heating units can work with an ambient down to -10c, it is amazing what heat you can get from a temperature of -10c (+50c) takes some getting your head around that one O0
If the whole sump was sealed from ambient but connected to the low pressure side of the system, and the oil changed to a compressor refigeration oil, there would be no problem I think if there was some leak by the piston rings.
My musings ;D
regards
Mike 8)
So I have to ask, would it simply make more sense to use an old single bore compressor as the engine? Wouldn't the cylinder and rings already be suitable for this sort of application?
I'm assuming we would still need the exhaust valve, but the intake could be removed and replaced with an injector.
Quote from: Matt Watts on 2014.05.16, 15:37:48
So I have to ask, would it simply make more sense to use an old single bore compressor as the engine? Wouldn't the cylinder and rings already be suitable for this sort of application?
I'm assuming we would still need the exhaust valve, but the intake could be removed and replaced with an injector.
Almost all compressor's use reed valve type setup's,which would not work in this case.there were very few that used mechanical valve's. There was one that i know of,built a long time ago(early 60's i believe) that used what was called a Dean rotary valve system. Suzuki motorcycle's also had a few modle's with this type of valve system on there two stroke engine's. We can use the standard 4 stroke engine with a few mod's-one i listed above. The other mod's needed would be to replace the inlet valve with the injection nozzle/injector setup,and regear the cam shaft to a 1:1 ratio to the crank or build up a second lobe on the exaust side of the cam 180* to the one already there-not so hard.This will give us an exaust phase every stroke.
But thinking some more on this,i believe i may have a far more efficient device to use as the engine,but getting my hand's on one may be tricky.Im going to leave this one out,until i can(if i can) get one
Hello all!
I will be happy to take part in this, I can not see any major problems to get this working as I am sure others allready have.
I am working with refrigeration of all kinds since 25 years, today I also work with everything you can find inside trains.. :D
As long as the output from the expansion inside the cylinder can power the compressor to turn a little more refrigerant into liquid state than was used in the expansion we will be home safe..
Thanks bf
Here is the perfect engine for this, I heard about it some time ago but never really thought too much about it, now it came to mind C.C
https://www.youtube.com/watch?feature=player_embedded&v=w27heVUxDQ8
just need the compressor, I wonder why they have not thought of it :-\
by using ambient heat and a 5:1 compressor, vola O0
problem is I don't think it is on the market yet
regards
Mike 8)
Quote from: Centraflow on 2014.05.17, 17:52:46
Here is the perfect engine for this, I heard about it some time ago but never really thought too much about it, now it came to mind C.C
https://www.youtube.com/watch?feature=player_embedded&v=w27heVUxDQ8
just need the compressor, I wonder why they have not thought of it :-\
by using ambient heat and a 5:1 compressor, vola O0
problem is I don't think it is on the market yet
regards
Mike 8)
Dear Mike.
Amazing !! We spent years developing steam engines to be as efficient as they could, using expansion. And now just waste it !! I was under the impression that the engine you linked to is solely pressure orientated ??
Perhaps you could correct me?
BTW. I could not see the exhaust !! Did you?
Cheers Grum.
Hi Grum,
the exhaust is on the head at the side, in the center of the head is the injector, the exhaust is recycled through a condenser and reheated again, it is a sealed system like what we are talking about, the only difference in reality is water to steam or gas to liquid.
I am sure a good machine shop could make this, it is not complicated, infact it is very simple but brilliant, so why have they not thought of using freon or other AC gas such as CO2 (higher pressure). Airconditioning used to be part of my business here in Spain, both design and installation along with central heating and gas installations.
regards
Mike 8)
Nice engine there Centraflow.
Now,as much as i look,i cant find at what preasure's different gasses turn to liquid-dose any one have a chart?. I have never delt with refrigeration system's befor,so have very limited knowledge(next to non) of how to turn the gas back into liquid. I know the gas needs to be recompressed,but is it cooled first,and then compressed back to liquid?.Dose it take less preasure to recompress the gas back to liquid,(after it has been cooled) than the preasure given by the liquid to gas inside the engine.
Yes, this is where I get confused too. Seems like time is being ignored somewhere. It takes a certain amount of time to heat the liquid just below its critical threshold, then the liquid is injected into the cylinder and nearly instantaneously it turns back to gas. After this, it takes time again to get the gas cooled down enough to recompress back to a liquid, then you're back heating it up again. So the part where you make power from the phase change is quick, but all the other stages are relatively slow. This tells me it would be pretty hard to loop, because you need to balance the quantity of material on both sides of the phase change and do it in essentially the same amount of time. Is that possible?
Maybe it's time to play a little numbers game here. Lets suppose I have one of those five cylinder engines and for every power stroke I need to inject 1cc of liquid. So for one complete revolution, I need 5cc. And lets say I need the engine to run at 1800 RPM to drive a generator shaft. Okay that's 30 revs per second each using 5cc, or 150cc of liquid per second. Now lets say the exhaust pressure for each cylinder is right around ambient and the volume is ohh, 200cc. So now I have 5*30*200 cc of gas to deal with every second, gas that I need to recompress back to liquid. That's 30,000 cc per second. 1cc = 1ml, so that's 30 Liters per second of gas? What kind of a compressor is it going to crunch down 30 Liters of gas per second, back to liquid? Seems like it would be a monster. Granted I'm pulling these numbers out of my rear end. I think the principal is sound though. Can this really work?
I think we are missing some explanation, to say the least. Matt you are about right if the exhaust exit pressure is not taken into consideration on the second cylinder, this is where we are missing information!!!
I am taking it that only even number cylinder engines can be used, 2,4,6,8 and @ 180 degrees, this was not explained very well in the pdf. I take it as this eg. in a 2 cylinder engine, one cylinder is in power stroke and the other in exhaust, energy will be used up in the power stroke to exhaust the other ??? so is this a 1:1??? No it is not, why, because we use gas phase and ambient (or other) heat and create up to 5:1, we now have a X4 gain.
When you look at say a fridge there are two pipes, flow and return. The flow pipe, thin pipe, is the liquid pipe, when the liquid passes into a higher volume area it changes phase to gas at that critical moment of volume change. The expansion is huge, far greater than the area it is expanding into, this is where we can take advantage of the phase change. This critical phase change moment is altered by heat, the liquid to gas phase change will cool but adding external heat at this point changes this volume relation of phase change, this is where we gain power.
I hope I have explained this, not very easy thing to explain, if you have questions ask and I will try to answer.
The important thing is even number cylinders, I think :-\ could be wrong on that but maybe the author can explain more, I see he is around here as a new member O0 also reduces problems of pass by of rings
regards
Mike 8)
Quote from: TinMan on 2014.05.18, 02:30:37
Nice engine there Centraflow.
Now,as much as i look,i cant find at what preasure's different gasses turn to liquid-dose any one have a chart?. I have never delt with refrigeration system's befor,so have very limited knowledge(next to non) of how to turn the gas back into liquid. I know the gas needs to be recompressed,but is it cooled first,and then compressed back to liquid?.Dose it take less preasure to recompress the gas back to liquid,(after it has been cooled) than the preasure given by the liquid to gas inside the engine.
Brad I will get back to you on your questions, I have to go out and pick up mother in law for lunch >:-)
regards
Mike 8)
Propane was mentioned as one of the "refrigerants" in the PDF.
some interesting info here
http://www.propanecarbs.com/propane.html
thx
Chet
Hi Chet
Thanks for the link O0
Yes LPG can be used as a refrigerant O0 you can see this as when you use a large amount from a bottle, the bottle freezes.
Brad, yes the gas is cooled first (a radiator) as on the back of a fridge, the more you can cool it the less energy is required to compress it into it's liquid phase, the reverse happens to change from liquid to gas, reduce pressure and heat it. This is where the gain comes by using the ambient temperature, this temperature is your fuel which can be multiplied by use of the gas/liquid phase change, COP >1, depending on design can be 5:1.
Yes it takes less pressure to liquefy the gas if it is cooled, think of aqualung tanks, to charge them with air you put them in a bath of water to keep them cool, pressure will heat and decompression will cool, small volume to high volume will cool and large volume to small volume will heat, so the volume of pipes and tanks is important to the efficiency.
Hope this has answered your questions.
regards
Mike 8)
I used to do design work for a couple of large Japanese companies until my heat exchanger patent ran out, that is used by all AC companies in the world, 97% efficient.
Grum
the exhaust on that engine is through the drive system, this would relate to the AC piston compressors and why I mentioned sealing the sump on an engine and connecting to the low pressure side of the loop. The oil and refrigerant are in a mix together on the low pressure side and why the oil has to be changed O0
regards
Mike 8)
it would be good to Know how much energy it takes to take propane vapor back to liquid,I am told there are typically
Huge losses during this process [compressor only 20% efficient [thx Rob Mason].
If the fellows running this replication claim are "topping it off" with bottled Liquid [do to leaks from an as yet not perfected motor design ] ,that could be an issue..?
thx
Chet
I am still thinking about the pass by of the cylinders if only one cylinder engine is used, I would need to calculate the pressure and vacuum differences in the system, and that can't be done without building it and measuring each part ??? or knowing the type of pump, volume of each part (vacuum/pressure in one cycle) then we have a variable which is the cylinder volume, oh well just have to suck it and see ;D
regards
Mike 8)
Quote from: Chet K on 2014.05.18, 11:28:31
it would be good to Know how much energy it takes to take propane vapor back to liquid,I am told there are typically
Huge losses during this process [compressor only 20% efficient [thx Rob Mason].
If the fellows running this replication claim are "topping it off" with bottled Liquid [do to leaks from an as yet not perfected motor design ] ,that could be an issue..?
thx
Chet
Yes it is also my concern and why it has to be a totally sealed system, everything welded up tight. :D
regards
Mike 8)
With all respect to Chris Hunter, the Replication claims outlined in this PDF were done autonomous of Chris's input.
I am quite sure Chris completely understands what this tech needs to work ,hopefully down the road
we will get a chance to see that........[that is the intent, open source]
Thx
Chet
So let me see if im in the ball park here. So looking at the pic below-we have our liquid tank/reservoir which has to have some room above the liquid level-so tank isnt totally full with liquid.From this tank ,the liquid would run down to an expansion tank(this is where liquid turns to gas?) From the expansion tank,the gas(which is under preasure)flow's into the cylinder when the inlet valve open's.This ofcourse forces the pistion down,and give us our power stroke.At BDC the inlet valve has closed,and as the piston starts to head back up,the gas flows out of the exaust valve.This then flow's to the pump,and the pump now pump's the hot gas to the condencer.The gas that is under preasure,then cool some what in the condencer,and return's back to liquid. ???????.
It seems to me that there must be some sort of preasure regulator between the tank and expansion chamber,to ensure that the preasure is higher on the pump,condencer,tank side of the system.
Quote from: TinMan on 2014.05.18, 12:24:21
So let me see if im in the ball park here. So looking at the pic below-we have our liquid tank/reservoir which has to have some room above the liquid level-so tank isnt totally full with liquid.From this tank ,the liquid would run down to an expansion tank(this is where liquid turns to gas?) From the expansion tank,the gas(which is under preasure)flow's into the cylinder when the inlet valve open's.This ofcourse forces the pistion down,and give us our power stroke.At BDC the inlet valve has closed,and as the piston starts to head back up,the gas flows out of the exaust valve.This then flow's to the pump,and the pump now pump's the hot gas to the condencer.The gas that is under preasure,then cool some what in the condencer,and return's back to liquid. ???????.
It seems to me that there must be some sort of preasure regulator between the tank and expansion chamber,to ensure that the preasure is higher on the pump,condencer,tank side of the system.
Dear Tinman.
Not quite correct, as I see it. The liquefied refrigerant is stored in an accumulator above the working cylinder and is admitted via a timed valve into the expansion (combustion if we were talking IC) chamber. The PDF was suggesting using the Spark plug hole as our means of injection. Upon admission the liquid instantly turns to it's gaseous state and provides the increase in pressure to move the piston. Return stroke then moves the gas to the condenser ready for our compressor to convert the gas back to a liquid state , thus on to the accumulator for the next cycle.
So it would seem that a single cylinder 4 stroke engine would not be suitable for this MO !! Far better a 2 stroke or as Mike suggests possibly a purpose built engine!! My own thoughts on this is maybe steal from our past!! Use a double acting steam engine cylinder so that part of the gaseous state can be compressed into the working cylinder, creating heat during the compression stroke which should seriously enhance the following expansion stroke !!
May I humbly suggest you guys look up the work of George B Brayton and his gradual combustion engine? As I see it his cycle is the reverse, instead of using heat to expand in the cylinder we are using a material that has two states, liquid and gaseous !!
Cheers Grum.
Hi Grum
I do have the accumulator above the engine cylinder-so that part is good.As i mentioned in a previous post,the 4 stroke engine can be modified to opperate as a 2 stroke engine quite easly. The reason i have the expansion chamber is to reduce the possability of ice forming on the engine itself. The inlet valve would then become your timed valve to allow the gas into the cylinder-this is ofcourse after the mod's,so as the inlet and exaust valve open every stroke. All the video's i have watched today on refrigeration system's ,show the pump befor the condencer ?.
https://www.youtube.com/watch?v=ZIlcn_qlQfc&list=HL1400419696&index=7
Hi Guy's
The expansion tank is not needed, the expansion tank is the cylinder block. The expansion tank as you call it is an accumulator (buffer) nothing more. Injected is liquid and not gas, as the piston goes down the volume increases and the liquid turns to gas at it's critical phase change, this creates huge expansion and drives the piston the other 90 degrees (we are told the liquid enters for the first 90 degrees).
When the outlet (exhaust) opens at BDC, the cylinder is then from the pressure side of the compresser to the vacuum side of the compresser (reverse), so we have a type of power stroke for 270 degrees or more.
For me it really has to be an even number of cylinders for this to work 2,4,6,8 etc. I can't at this moment see a 1 cylinder running efficiently, it has many problems.
regards
Mike 8)
Sorry very rough
mike 8)
Mike suggested a scroll compressor might be best suited to this system, but no efficiency figure given that I can find with a quick search. Compression efficiency of gas back to liquid will be critical in the operation of a closed loop RPE.
http://en.wikipedia.org/wiki/Scroll_compressor#Efficiency
http://www.emersonclimate.com/en-US/products/compressors/scroll_compressors/Pages/scroll_compressors.aspx
Dear all.
That was a particularly interesting afternoon indeed !!
I am now more eager than ever to start upon a replication. Many thanks to Tinman, Centraflow and evolvingape for the chat and subsequent Skype conversation !!
After having a chat with my friend at the LPG conversion garage last week who suggested the use of a Petrol/Gasoline injector in place of the LPG injector. BTW nothing was mentioned about what I was doing !! ;) His suggestion based upon the injectors being able to handle a liquid up to a pressure of 6 to 7 Bar.
I now have most of the ingredients to hand still need to find a condenser and a few fittings !!
Cheers Grum.
I was musing to myself and had an idea for this system..
Why don't we run an ICE generator with an LPG conversion as a heat engine, basically burning the LPG like normal. Radiator temperature should be around 80 - 90 C..
Then we run a second ICE generator with an RPE conversion and loop the two systems together so that we can take advantage of all that heat from the LPG ICE.
Should create quite a large thermal potential difference and both systems run off same fuel, but with opposing heat cycles.
What do you guys think ?
Quote from: evolvingape on 2014.05.18, 23:25:03
I was musing to myself and had an idea for this system..
Why don't we run an ICE generator with an LPG conversion as a heat engine, basically burning the LPG like normal. Radiator temperature should be around 80 - 90 C..
Then we run a second ICE generator with an RPE conversion and loop the two systems together so that we can take advantage of all that heat from the LPG ICE.
Should create quite a large thermal potential difference and both systems run off same fuel, but with opposing heat cycles.
What do you guys think ?
I had a very similar thought after our convo yesterday. But i was thinking of using a 2 cylinder engin,and have one cylinder run of the LPG,and the other on the RPE.If we use an engine that has the two cylenders side by side,then the heat from the cylinder running on LPG,would heat the cylinder running the RPE system.
Hi Guy's
just got back home from a 4hr round trip to our apartment at the beach, and I hear Chet has been chatting up my wife ;D sorry to miss you
That idea is quite good, but still my concern is leakage. This system must be 100% gas tight, if it is and we have a good delta T we will be in business, the heat sink could be a home made solar panel with some copper tubes painted matt black. In theory a 5:1 thermal to power ratio will produce excess even with power train losses.
So we must sort out the leakage problem first of all.
regards
Mike 8)
Good stuff Tinman I like it, however I see your idea as phase two of the project. An integrated engine with both LPG and RPE complimenting..
Phase one would be to build two separate 2 stroke engines, one running on LPG and the other running on RPE. The cooling systems must be cross connected so the hot water from the LPG runs around the RPE engine, and the RPE (cold engine) coolant system runs around the the LPE (hot) engine. In a single engine the coolant fluid channels are connected and you will lose your heat energy potential difference.
The other concern I have with your idea Tinman is that it may be hard to initially balance the energy going into each cylinder causing shear forces on the crank under load as it hunts, potentially leading to critical failure. It is doable, however I feel it will be better as a custom designed engine so you can separate the micro channels and have two thermal systems in the same engine block.
So in summary split the LPE hot water into two streams, one that goes round the RPE warming it up, and the other that directly heats the RPE exhaust gas before compressor condenser to maximise heat energy transferred to the refrigerant gas and thus maximising the reduction in compression costs back to liquid.
Probably best run as a hybrid engine. The LPE providing drive as normal, and the RPE charging a KERS type flywheel system and running an alternator. So when you run out of fuel (LPE which will deplete), you can still drive on stored electrical energy and electric drive motors to the LPG refuel station.
As an add on Mike, the RPE is the heatsink engine, and the thermal input providing high delta T is the LPE hot engine. The potential difference could well be in the 80 - 90 Centigrade range.. plenty!
EA, agreed.
Can we put some ideas forward on sealing. When I can get a minute I will redraw that hand sketch so as it can be seen ;D
regards
Mike 8)
Quote from: Centraflow on 2014.05.19, 17:04:42
EA, agreed.
Can we put some ideas forward on sealing. When I can get a minute I will redraw that hand sketch so as it can be seen ;D
regards
Mike 8)
Dear Mike.
I really don't think the Piston sealing is much of an issue!! I have been using Nitrile "O" rings in place of piston rings on some of my Model engines for years now. And yes, they actually survive temperatures well above their 100 deg C rating !!
For the RPE however, we are not going to see temperatures anywhere near that. As I see it, it will be the valve stems that will require attention. But possibly by using valve stem seals in reverse i.e. just below the underside of the head in the inlet/outlet tracts would probably seal the engine towards your 100% goal.
Cheers Grum.
Quote from: Centraflow on 2014.05.19, 17:04:42
EA, agreed.
Can we put some ideas forward on sealing. When I can get a minute I will redraw that hand sketch so as it can be seen ;D
regards
Mike 8)
Mike-see reply 26 on this thread.
Quote: I have been giving this some thought,and think i have a cheap way to convert a standard gas engine to do what you want it to do.The biggest problem is like ION mentioned-blow by. If we take a standard single cylinder engine(e.g,honda,chonda,robbin,etc),there would be enough meat on the piston to remove the standard piston ring's,and machine one of the piston ring grooves to take a hydraulic ram seal. The cylinder can then be polished using a buffer disk of right diameter,and cutting compound- used to cut and polish car paint.This will give the cylinder a mirror finish to ensure a perfect seal.These seal's will handle a quite high temp,and i dont think this type of setup would generate much heat at all within the engine-in fact, i think there would be freezing problem's insted.
This is well within our capability,and will work just fine.
Agreed Tinman, sealing should not be a problem. There is a wide range of O ring sizes available and the temperature range is more than suitable for what we want to do:
http://www.bearingboys.co.uk/O-rings-1050-c
http://www.bearingboys.co.uk/O-rings_Technical_Data-60-a
A couple of small 2 stroke generators with water cooling would be ideal.. if I could find them.. struggling at the moment all the 2 strokes seem to be air cooled and the 4 strokes are water cooled.
Might be a good idea to add a couple of back up rings in a suitable material as well.
Not found what I am looking for yet but these two designs are interesting:
http://thekneeslider.com/ecomotors-opoc-two-stroke-engines-opposed-piston-opposed-cylinder/
http://thekneeslider.com/pivotal-piston-water-cooled-two-stroke-engine/
A 2 stroke engine??. What about the transfer and exaust port's in the cylinder ?.
I had less information when I posted before about the two stroke, now I have more information and need to reassess. I will sleep on it, but I am no longer thinking 2 stroke..
Thanks for pointing that out Tinman. O0