I think the "ls" parameter is meant to be the length where magnetic field cuts cylindrical coil.
The thickness of magnet.

Quote from: teslaalset on February 15, 2011, 03:51:33 PM
The whole setup is quite critical but with the default parameter set, Turtur gave us a 'realistic' model. Wire diameter is the one that should be chosen a realistic value.
You can obtain much more output, as you showed, but then you need superconducting wire.
Some parameter combinations will not give you any output, as you showed with some of your settings. It's all about finetuning into realistic values here.

@neptune,
You can use the program and the parameter file to change the magnet dimensions and see whether you can find your desired outcome. It's pretty simple, you don't need to be a computer wizzerd.

@ teslaalset,

"I don't know about the 'realistic' model..."

di => {di:=spool diameter, m} (this is NOT the wire diameter {Dd:=wire diameter, m} OR wire conductivity of cupper)

When we put:

(di) = 0.70m => 88825909 Kw
(di) = 0.71m => 0.01 Kw

This meen, when the coil diameter = 0.7 m (27.559") we have an output of 88000000 Kw AND with the coil ONLY 0.01m (0.394") bigger we get 0.01 Kw ... this make no sense to me.

"...finetuning into realistic values here..." a coil of 0.7m is big, agree, BUT IT'S NOT a un-realistic values. (like 5m and more would probably be)

And what about "superconducting wire" ? It's not about superconducting parameter but about the size (diameter) of the coil only.... this don't influence, from what i understand, any "superconducting" behavior...



I'm not sure to understand you, you're probably good in superconductivity field, not me ... could you explain how superconductivity is at stake in this program ... thanks.



LightRider


PS.: you can get any type of result, if a program is poorly designed or if the approximation done in the progam is unknown to the users... you can finetune as much as you want...  but first you have to know the program limite"

Quote from: LightRider on February 16, 2011, 09:50:20 AM


@ teslaalset,

"I don't know about the 'realistic' model..."

di => {di:=spool diameter, m} (this is NOT the wire diameter {Dd:=wire diameter, m} OR wire conductivity of cupper)

When we put:

(di) = 0.70m => 88825909 Kw
(di) = 0.71m => 0.01 Kw

This meen, when the coil diameter = 0.7 m (27.559") we have an output of 88000000 Kw AND with the coil ONLY 0.01m (0.394") bigger we get 0.01 Kw ... this make no sense to me.

"...finetuning into realistic values here..." a coil of 0.7m is big, agree, BUT IT'S NOT a un-realistic values. (like 5m and more would probably be)

And what about "superconducting wire" ? It's not about superconducting parameter but about the size (diameter) of the coil only.... this don't influence, from what i understand, any "superconducting" behavior...



I'm not sure to understand you, you're probably good in superconductivity field, not me ... could you explain how superconductivity is at stake in this program ... thanks.



LightRider

@LightRider,

My main issue with 'realistic models' is that copper wire does have a certain ohmic resistance.
If you apply too many KW in a device, the copper wire will be destroyed because part of the many KW will be used to heat up the copper wire.
I mentioned super conductive wires because when you cool down an aluminum wire below 1.2 degrees Kelvin, the wire becomes super conductive and loose all of its ohmic resistance (resistance is ZERO!).

Besides, I don't think that the applied magnet (with a diameter of 3.9 cm) in combination with a coil of 0.7 meters will generate 88825909 KW, simply because the magnetic fields that cross the coil winding will in that case be too weak.

So, the model looks nice but I doubt whether you can use it with all kind of desired dimensions.

Here's the field strength profile of a 4cm N52 NdFeB type magnet in air.
You can see that around approximately 3 times the diameter the field strength is almost completely gone.

(the purple circle is the actual magnet)

Quote from: teslaalset on February 16, 2011, 10:44:21 AM
Here's the field strength profile of a 4cm N52 NdFeB type magnet in air.
You can see that around approximately 3 times the diameter the field strength is almost completely gone.

(the purple circle is the actual magnet)

Thanks teslaalset, understand better what you meant.
LightRider