PopularFX
Home Help Search Login Register
Welcome,Guest. Please login or register.
2024-03-29, 07:58:14
News: Registration with the OUR forum is by admin approval.

Pages: [1]
Author Topic: Toroidal and Polodial - Which is Which?  (Read 19126 times)

Group: Administrator
Hero Member
*****

Posts: 3198
It's not as complicated as it may seem...
I would strongly suggest we follow the Tokamak scientists, as they got the terminology right imo.

If we use TFC for "Toroidal Field Coil", and PFC for "Poloidal Field Coil", there is absolutely no confusion as to which coil is being referred to. This terminology refers to the field which is being produced, not which plane the coil sits in. From this the coil's position can be deduced without error.

.99
   
Group: Guest
Let us make sure when we use the words poloidal and toroidal that we define the usage.

When someones says 'poloidal winding' it refers to the 'winding', not the field.

Too often we mention one thing and mean another. Too often, we measure one thing and assume the other.
Example: We measure the electric vector and assume what the magnetic is doing. The assumption is not always correct.

Both patent drawing examples are correct. One refers to the windings the other refers to the field created.

The military had it right and their usage doesn't conflict with usage by physicists. The Tokamak users also refer to windings as to what they are and not what they create. It depends on the conversation or document. This is just another example of language being more flexible than the users.

In my opinion...

Naming a coil for what field we think it will create is a bad practice. It works well for a well defined device. This practice has no place when discussing a device with unknown operation.
   
Sr. Member
****

Posts: 276
H All,
 In wave propagation (radio transmissions) you would refer to a ppi (polar pattern indicator) for the measured field strength when an assumption/result could be completely unknown. The orientation of the radiating element(s) is the only fixed part of the equipment and its this used as the  reference. As WW says the fields direction can be so misleading if there is anything missed or unknown.
Imho reference to the coil(s) location on the device IS to be referred to for clarity. The field may be affected by parasitic elements and these may not be so apparent.
Steve.
   

Group: Administrator
Hero Member
*****

Posts: 3198
It's not as complicated as it may seem...
H All,
 In wave propagation (radio transmissions) you would refer to a ppi (polar pattern indicator) for the measured field strength when an assumption/result could be completely unknown. The orientation of the radiating element(s) is the only fixed part of the equipment and its this used as the  reference. As WW says the fields direction can be so misleading if there is anything missed or unknown.
Imho reference to the coil(s) location on the device IS to be referred to for clarity. The field may be affected by parasitic elements and these may not be so apparent.
Steve.

Understood, however this is completely outside the bounds of the toroid discussion. Ignoring the superposition effects, the fields within and around a toroid configured with both orthogonal windings, are well established and defined.

.99
   

Group: Administrator
Hero Member
*****

Posts: 3198
It's not as complicated as it may seem...
Let us make sure when we use the words poloidal and toroidal that we define the usage.

When someones says 'poloidal winding' it refers to the 'winding', not the field.
Agreed. By the same token, if someone says 'TFC' it would be in reference to the 'poloidal winding'.

Quote
Both patent drawing examples are correct. One refers to the windings the other refers to the field created.
Respectfully, this is not so. Both diagrams are labeled and/or referred to in the patent text as "coils" or "windings", so it is impossible to conclude that they are both correct. In the technical sense, clearly one is not correct, and that would be the Delvecchio patent I posted. Had he included the word "field", he would be correct. Perhaps he got lazy and dropped "field" from the term, or perhaps this has become the convention. I would suspect the latter, as everything I've come across uses this terminology. Interestingly, the Prueitt patent references the Delvecchio patents.

Quote
The Tokamak users also refer to windings as to what they are and not what they create.
Again, this is simply not so. Have a look again at the Tokamak diagram I posted (and several others included below). I've done additional research and in reference to the iter and JET Tokamaks, and others, they ALWAYS refer to the fields when referencing the coils. I'd be interested to see your research and any reference which proves the contrary. If they do exist, they would certainly occupy only a tiny minority.


From the glossary of iter terms here: http://www.iter.org/glossary
"iter" being the world's largest Tokamak under construction:

Poloidal Direction:    
Movement in the vertical plane intersecting the plasma torus along projections in that plane of any of the tokamak's nested toroidal flux surfaces.

Poloidal Field:    
The magnetic field generated by an electric current flowing in a ring. In toroidal devices, the magnetic field that encircles the plasma axis. (i.e. loops around the torus the short way.)

Poloidal Field Coils:    
Components of a tokamak that assist in stabilizing the plasma. In ITER, the Poloidal Field coil system consists of six horizontal coils placed outside the Toroidal Magnet structure.


Toroidal Direction:    
In a doughnut-shaped torus, the direction parallel to the large circumference.

Toroidal Field:    
The magnetic field generated by an electrical currrent flowing around a torus.

Toroidal Field Coils:    
Components of a tokamak that assist in stabilizing the plasma, by creating a 'magnetic bottle' for confinement. In ITER, the Toroidal Field coil system consists of 18 D-shaped vertical coils placed around the Vacuum Vessel.

Another good document from iter.

From the JET website, a good document "The Science of JET" which clearly indicates the coil terminology used throughout in Tokamak research. There are many good documents discussing the project. JET is the "Joint European Torus", Europe's largest fusion device. I think we would be remiss in saying that these many Tokamak physicists got the coil terminology wrong.

There are hundreds of references out there on Tokamak technology and "plasma confinement" using the orthogonal coil method, and in my findings, they all agree on the coil reference terminology noted in the glossary above and all the illustrations that can be found on the Tokamak. Included below are a few more of those illustrations:

.99
   
Group: Guest
Understood, however this is completely outside the bounds of the toroid discussion. Ignoring the superposition effects, the fields within and around a toroid configured with both orthogonal windings, are well established and defined.

.99

Only with currently practiced signal injection.

Regardless, my expectations of important fields in a TPU are that they are either nulls or negative. I have decided this because of evidence in the TPU videos.

1. On the demo of one of the smaller TPUs, on the glass table top, look at what he applies to the TPU. I can only presume it is to initialize something. The device is not a simple magnet. It looks more like a magnet in a metal shell. Perhaps the back side of a speaker. If this is the case, he is applying what is understood as a null in a magnetic field?
2. The LTPU output terminals are connected to poloidal windings but both leads enter on the same side. This can only be done if both wires are wound in opposite directions (bucking toroidal field).
3. Small toroid... (Yes, I know many are blind to this fact but I can't change what is obvious to me) the poloidal winding reverses direction at the half way point. Yet another bucking toroidal field. He applies the magnet at this point where these fields crash or compress.

If we apply 'all usage of the words poloidal or toroidal will reference the field it creates' then how can this work when the fields needing discussion are are already erroneously called 'nulls' or 'cancellations'? (It is impossible to cancel a magnetic field. The 'NET' magnetic field may be zero but the fields creating that net do not disappear.)

I won't be applying this new definition as I have enough trouble with the other redefines and terminology inventions centered around TPUs.

I know the following mean something different to others. I can't change that and won't attempt to.

TPU
Collector
Control Coil
Resonance
Rotations in a TPU
Harmonic
and now Poloidal & Toroidal winding/coil.

I can agree with the usage when referring to fields. I just don't think such fields are the most important aspects in a TPU.

-----

"Agreed. By the same token, if someone says 'TFC' it would be in reference to the 'poloidal winding'." -.99

Yes. That is and always has been understood by me.

"I think we would be remiss in saying that these many Tokamak physicists got the coil terminology wrong." -.99

I'm not disagreeing with them or the definitions you posted. Neither did the military trainers who pounded these definitions into my head over thirty years ago.

There is no point in continuing this. I will just make extra effort to clarify my comments when they relate to a complex shape.
   

Group: Experimentalist
Hero Member
*****

Posts: 567
Are you guys just trying to confuse an old buzzard like me. ::)
It appears to me you are both saying the same thing.  If I refer to a winding and I call it poloidal it is a large selonoidal type winding think loop antenna.  If I refer to a toroidal winding, I mean it is wound in a toroidal fashion, think donut. If refering to a field created by the winding then it would be just the opposite. Is this correct is this what you guys are saying? If so I think it is what we all thought all along.
Please don't confuse me.  :o


---------------------------
"Whatever our resources of primary energy may be in the future, we must, to be rational, obtain it without consumption of any material"  Nicola Tesla

"When bad men combine, the good must associate; else they will fall one by one, an unpitied sacrifice in a contemptible struggle."  Edmund Burke
   
Group: Guest
Please don't confuse me. ::)

All of the graphics posted in the last couple of days are correct. Just pay special attention to the text.

Sorry for the confusion.
   

Group: Administrator
Hero Member
*****

Posts: 3198
It's not as complicated as it may seem...
Are you guys just trying to confuse an old buzzard like me. ::)
It appears to me you are both saying the same thing.  If I refer to a winding and I call it poloidal it is a large selonoidal type winding think loop antenna.  If I refer to a toroidal winding, I mean it is wound in a toroidal fashion, think donut. If refering to a field created by the winding then it would be just the opposite. Is this correct is this what you guys are saying? If so I think it is what we all thought all along.
Please don't confuse me.  :o

That's a good illustration of the problem Room. I honestly don't know from your description above, which coils you are actually referring to.

.99
   

Group: Experimentalist
Hero Member
*****

Posts: 567
.99 thats why pictures and drawings are so nice for everyone. :)

And I'm wondering who's confused here?


---------------------------
"Whatever our resources of primary energy may be in the future, we must, to be rational, obtain it without consumption of any material"  Nicola Tesla

"When bad men combine, the good must associate; else they will fall one by one, an unpitied sacrifice in a contemptible struggle."  Edmund Burke
   

Group: Administrator
Hero Member
*****

Posts: 3198
It's not as complicated as it may seem...
.99 thats why pictures and drawings are so nice for everyone. :)

And I'm wondering who's confused here?

Room,

Exactly why agreed terminology needs to be established and used. I am confused as I already said about which coils are which, by your description. A statement is made using toroidal or poloidal, then followed by another statement that seems to contradict the previous.

Try again ;)

.99
« Last Edit: 2011-01-01, 20:05:53 by poynt99 »
   

Group: Experimentalist
Hero Member
*****

Posts: 567
Just look at your graphic above jg951132c.png says it right there. I don't understand your confusion?
And please don't take this badly, we do need to define terms so we are all on the same page. ;)


---------------------------
"Whatever our resources of primary energy may be in the future, we must, to be rational, obtain it without consumption of any material"  Nicola Tesla

"When bad men combine, the good must associate; else they will fall one by one, an unpitied sacrifice in a contemptible struggle."  Edmund Burke
   

Group: Administrator
Hero Member
*****

Posts: 3198
It's not as complicated as it may seem...
Are you guys just trying to confuse an old buzzard like me. ::)
It appears to me you are both saying the same thing.  If I refer to a winding and I call it poloidal it is a large selonoidal type winding think loop antenna.  If I refer to a toroidal winding, I mean it is wound in a toroidal fashion, think donut. If refering to a field created by the winding then it would be just the opposite. Is this correct is this what you guys are saying? If so I think it is what we all thought all along.
Please don't confuse me.  :o

If I interpret this correctly, you are saying what I originally said. However, you would need to either insert "field" in there, or drop it and assume you are referring to the field, which by your post I don't think you were. See the confusion? You and WW are in disagreement at this point.

.99
   

Group: Experimentalist
Hero Member
*****

Posts: 567
Poynt I believe WW is saying the same thing, I don't think I disagree with him but I do agree with the graphic I mentioned above, Whoever that is agreeing with?
It is the way I mean things when I use the terms.  

I did use the term field in the quote?


---------------------------
"Whatever our resources of primary energy may be in the future, we must, to be rational, obtain it without consumption of any material"  Nicola Tesla

"When bad men combine, the good must associate; else they will fall one by one, an unpitied sacrifice in a contemptible struggle."  Edmund Burke
   

Group: Administrator
Hero Member
*****

Posts: 3198
It's not as complicated as it may seem...
@ALL: In the following diagram posted on WW's bench in "Reference Material", do you agree with the shown terminology used to reference the coils / windings?



.99
« Last Edit: 2011-01-01, 20:06:44 by poynt99 »
   

Group: Administrator
Hero Member
*****

Posts: 3198
It's not as complicated as it may seem...
Poynt I believe WW is saying the same thing, I don't think I disagree with him but I do agree with the graphic I mentioned above, Whoever that is agreeing with?
It is the way I mean things when I use the terms.  

I did use the term field in the quote?

I don't think you and WW are agreeing at all.

The word "field" needs to be used with "coil" and either "toroidal" or "poloidal". You didn't use it that way.

Please respond with your opinion. I think you will see that you disagree with the diagram, if I interpreted your posts correctly.

.99
« Last Edit: 2011-01-01, 20:07:40 by poynt99 »
   

Group: Administrator
Hero Member
*****

Posts: 3198
It's not as complicated as it may seem...
Room, here is your post again:

Are you guys just trying to confuse an old buzzard like me. ::)
It appears to me you are both saying the same thing.  If I refer to a winding and I call it poloidal it is a large selonoidal type winding think loop antenna.  If I refer to a toroidal winding, I mean it is wound in a toroidal fashion, think donut. If refering to a field created by the winding then it would be just the opposite. Is this correct is this what you guys are saying? If so I think it is what we all thought all along.
Please don't confuse me.  :o

I would say from your description, you are not in agreement with the above diagram, therefore in disagreement with WW.

.99
   

Group: Experimentalist
Hero Member
*****

Posts: 567
.99
I do agree with you that the terminology is wrong in that drawing, but I thought WW said the same thing? Maybe I didn't percieve what I read correctly?

Like I said I agree with the graphic above (jg951132c.png) and I thought WW said the graphics were correct as well?(not the one above I disagree with)
All of the graphics posted in the last couple of days are correct. Just pay special attention to the text.

Sorry for the confusion.


---------------------------
"Whatever our resources of primary energy may be in the future, we must, to be rational, obtain it without consumption of any material"  Nicola Tesla

"When bad men combine, the good must associate; else they will fall one by one, an unpitied sacrifice in a contemptible struggle."  Edmund Burke
   

Group: Administrator
Hero Member
*****

Posts: 3198
It's not as complicated as it may seem...
WOW a lot of posts before I could respond!

.99
I do agree with you that the terminology is wrong in that drawing, but I thought WW said the same thing? Maybe I didn't percieve what I read correctly?

That picture was/is posted in WW's Bench thread as to how he refers to the coils. That is what started this whole discussion. So that is WW's preferred terminology, and also is contrary to what I've always thought as well. So I am in agreement with you, not with WW's diagram.

However, it would appear that WW's diagram IS correct, IF talking strictly of the coil's position or plane and not the field. "Toroidal" means as a torus, so anything laying in the toroidal plane axis (i.e following the large radial path of the doughnut) should be called "toroidal".

And of course vice-versa in all aspects for the poloidal plane.

Now, if we say "Toroidal Field Coil" OR "Poloidal Field Coil", these terms mean a different thing; the coils are designated by the field that they produce rather than their physical orientation.

So, the options we have are to say "Toroidal Coil" which refers to coil 12a/12c in the drawing, or we can say "Toroidal Field Coil" which refers to coil 12b in the drawing. If you say one and actually mean the other, then we're back to confusion once again.

It sucks, but that is the facts Jack!

.99
   

Group: Experimentalist
Hero Member
*****

Posts: 567
I have to agree with you Poynt, guess I'm on your side but I really hate to pick sides. In my case I will continue to use the terminology as you see it just so I don't confuse myself. If I confuse WW I am sorry.
 :)


---------------------------
"Whatever our resources of primary energy may be in the future, we must, to be rational, obtain it without consumption of any material"  Nicola Tesla

"When bad men combine, the good must associate; else they will fall one by one, an unpitied sacrifice in a contemptible struggle."  Edmund Burke
   

Group: Administrator
Hero Member
*****

Posts: 3198
It's not as complicated as it may seem...
I have to agree with you Poynt, guess I'm on your side but I really hate to pick sides. In my case I will continue to use the terminology as you see it just so I don't confuse myself. If I confuse WW I am sorry.
 :)


Room,

If you understand the difference between the two ways one can reference a particular coil, and use the terminology appropriately, no one will be confused.

It's not about picking sides in this case, it's simply about siding with what is technically correct.

.99
   
Sr. Member
****

Posts: 276
Hi,
 Can I say at present I am text only so pictures ....?
Anyhow the field can deviate from the expected in certain conditions. I  should have mentioned mag loop antenna in the reference.. my bad.
However there are directable fields from static coils by means of phase feeding offsets. The coils are stationary and the field can be manipulated in its direction.
To keep things in the KISS ideal we should simply state anything
relevant, precisely and clearly.
 I cant think of anyone at 'our' discussing anything so poorly that it needs running by a parser lol.
Steve.
   
Group: Guest
I have to agree with you Poynt, guess I'm on your side but I really hate to pick sides. In my case I will continue to use the terminology as you see it just so I don't confuse myself. If I confuse WW I am sorry.
 :)


No need to apologize. I'm not confused. Just be aware that when I say 'winding' I mean 'winding'. The same if I use the word 'field'.

While it is true that a poloidal winding produces a toroidal field, and a toroidal winding produces a poloidal field, these are not always the case.

There is enough confusion created by the use of the word 'toroid'. We call a device shaped like a doughnut a toroid. That is the same as calling a compass a 'north'.

Isn't all this stuff fun?

I will agree with the need for pictures for clarification.
Since I have little time for drawings, future comments relating to complex shapes will be limited.
   

Group: Administrator
Hero Member
*****

Posts: 3198
It's not as complicated as it may seem...
Hi,
 Can I say at present I am text only so pictures ....?
Anyhow the field can deviate from the expected in certain conditions. I  should have mentioned mag loop antenna in the reference.. my bad.
However there are directable fields from static coils by means of phase feeding offsets. The coils are stationary and the field can be manipulated in its direction.
To keep things in the KISS ideal we should simply state anything
relevant, precisely and clearly.
 I cant think of anyone at 'our' discussing anything so poorly that it needs running by a parser lol.
Steve.

szaxx, WW,

Good grief guys! Why complicate things?   >:(

As long as we all understand and agree to an acceptable nomenclature, there can not be any confusion nor misinterpretations! And there would be no need for pictures or illustrations. We're long past the picture-book phase, so let's agree and move on. This is getting ridiculous.

Have I not laid out the proposed nomenclature and and it's meanings clearly enough to understand and use ?

.99
   
Sr. Member
****

Posts: 276
Hi,
.99, you have said what should be done and I agree. There isn't much misinterpretation here as all state quite clearly their objectives, as pointed out there are others that gloss over and this requires a read of all the info and diagrams, patents are a fine example.
Occasionally language translation throws things into disarray.
A small misrepresentation addresses another request for clarification and this is easily asked for. Theres no problem with this and as this happens in posts worldwide. The 'who is right' part  is irrelevant, what is technically correct, IS.
Historically, referencing this in mind the world isn't flat.
Steve.
   
Pages: [1]
« previous next »


 

Home Help Search Login Register
Theme © PopularFX | Based on PFX Ideas! | Scripts from iScript4u 2024-03-29, 07:58:14