[Getdp] 2D axisym. coil

Frederic Trillaud Pighi ftrillaudp at pumas.iingen.unam.mx
Mon Aug 10 17:14:39 CEST 2015


Dear Peter,

It reminds me of the integral constraint in COMSOL. I do not know in GetDP. As far as I know, you can provide constant values for the constraint but I am not sure how you can use out of the box a function to implement the integral constraint. It may require some extra-implementation. The other option is to solve it as an extra equation: Int (Jext+sigma*E-J) = 0 where J is an homogeneous current density J = I/Omega_coil. Not sure if it makes sense for your problem.

Hopefully, someone has an appropriate answer to your problem. I would be interested to know how it could be implemented. I may need it down the road.

Best,

Frederic



> On Aug 9, 2015, at 4:28 PM, Peter Kis <md2z34 at gmail.com> wrote:
> 
> Dear Frederic,
> 
> a big thank to you for helping me out of this. The model with your modifications works like a charm. I am amazed how could you figured out the problem with the initial conditions. How could you catch this? 
> 
> I compared the results given by getdp with COMSOL and it's a perfect match! I am very pleased.
> 
> I continue developing this model. Because I still need to add a special constraint which should enforce not the external current density to the coil but the net current. That is int_Omega_coil (Jext + sigma*E) = I, where E is the electric field E= -dA/dt. It's a kind of iteration thing because the total net current depends on the result (A). Do you think such constraint is possible in getDP? 
> 
> Thanks again,
> 
> Kind Regards
> 
> 
> Peter
>   
> 
> On Sun, Aug 9, 2015 at 1:52 AM, Frederic Trillaud Pighi <ftrillaudp at pumas.iingen.unam.mx <mailto:ftrillaudp at pumas.iingen.unam.mx>> wrote:
> Dear Peter,
> 
> Here it goes. I made some changes (transformation with an outer shell,
> killed the initial time value of A, you should not need it) and did some
> tests so the parameters of current density etc. have been changed. It
> should work fine now.
> 
> Best,
> 
> Frederic
> 
> 
> On Sun, 2015-08-09 at 00:27 +0200, Peter Kis wrote:
> > I am sending the model files. Thanks for your time.
> >
> >
> > Peter
> >
> >
> > On Sat, Aug 8, 2015 at 11:02 PM, Frederic Trillaud
> > <ftrillaudp at pumas.ii.unam.mx <mailto:ftrillaudp at pumas.ii.unam.mx>> wrote:
> >         Send me back your files, I will take a look at it over the
> >         weekend to
> >         see if I can pin the problem.
> >
> >         Frederic
> >
> >
> >         -----Original Message-----
> >         From: Peter Kis <md2z34 at gmail.com <mailto:md2z34 at gmail.com>>
> >         To: Frederic Trillaud <ftrillaudp at pumas.ii.unam.mx <mailto:ftrillaudp at pumas.ii.unam.mx>>
> >         Cc: getdp at geuz.org <mailto:getdp at geuz.org>
> >         Subject: Re: [Getdp] 2D axisym. coil
> >         Date: Sat, 8 Aug 2015 22:43:11 +0200
> >
> >         Dear Frederic,
> >
> >
> >         thanks for your reply. There must be something else here,
> >         because
> >         VolAxiSqu hasn't helped.
> >
> >
> >         I think the time function in my code might be okay, because it
> >         seems to
> >         work fine for Jacobi Vol.
> >
> >
> >         Cheers,
> >
> >
> >         Peter
> >
> >
> >         On Sat, Aug 8, 2015 at 5:51 PM, Frederic Trillaud
> >         <ftrillaudp at pumas.ii.unam.mx <mailto:ftrillaudp at pumas.ii.unam.mx>> wrote:
> >                 Dear Peter,
> >
> >                 I had a similar problem, you should try VolAxiSqu. It
> >         solves my
> >                 issue on
> >                 the axis of symmetry.
> >
> >                 Jacobian
> >                 {
> >                  {// Dimension ND regions in plane
> >                   Name AxiJacobian;
> >                   Case
> >                   {
> >                    {
> >                     Region infiniteBoundaryRegion;
> >                     Jacobian
> >         VolAxiSquSphShell{0.95*infiniteBoundaryInnerRadius,
> >                 1.05*infiniteBoundaryOuterRadius};
> >                    }
> >                    {
> >                     Region All;
> >                     Jacobian VolAxiSqu;
> >                    }
> >                   }
> >                  }
> >                 }
> >
> >                 To apply the current density, you need to use time
> >         function that
> >                 will be
> >                 multiply to your current density. You have to
> >         implement it in
> >                 the
> >                 Constraint.
> >
> >                 Constraint
> >                 {
> >                 {
> >                   Name currentDensityCondition;
> >                   Case
> >                   {
> >                    {
> >                     Region inductorRegion;
> >                     Value currentDensity[];
> >                     TimeFunction timeFunction[];
> >                    }
> >                   }
> >                  }
> >                 }
> >
> >                 I use the conditional operators to create the time
> >         function:
> >
> >                 "timeFunction[] = If condition Then statement Else
> >         statement;"
> >                 is then
> >                 in conditional operators:
> >                 timeFunction[] = (condition) ? statement : statement;
> >
> >
> >         http://www.c4learn.com/c-programming/c-conditional-operators/ <http://www.c4learn.com/c-programming/c-conditional-operators/>
> >
> >                 Good luck,
> >
> >                 Frederic
> >
> >                 -----Original Message-----
> >                 From: Peter Kis <md2z34 at gmail.com <mailto:md2z34 at gmail.com>>
> >                 To: getdp at geuz.org <mailto:getdp at geuz.org>
> >                 Subject: [Getdp] 2D axisym. coil
> >                 Date: Sat, 8 Aug 2015 16:57:49 +0200
> >
> >                 Dear getDP list members,
> >
> >
> >                 I am still struggling with my first model in getDP,
> >         which would
> >                 be a
> >                 single turn coil on 2D axisymmetric plane.
> >
> >
> >                 Now, at least I get something, but I don't like what I
> >         get. I am
> >                 not
> >                 sure how to apply the time dependent excitation
> >         current density
> >                 to the
> >                 coil. Therefore I took something over from CoreMassive
> >         model
> >                 (found on
> >                 the Internet).
> >
> >
> >                 As you can see in the attached pictures the magnetic
> >         vector
> >                 potential
> >                 for the pure 2D model (with Jac Vol) looks good but
> >         for the
> >                 axisym model
> >                 (with Jac VolAxi) it looks terrible.
> >
> >
> >                 Definitely there is still something here what I miss.
> >
> >
> >                 Any comment is highly appreciated.
> >
> >
> >                 Thanks in advance,
> >
> >
> >                 Peter
> >
> >
> >                 _______________________________________________
> >                 getdp mailing list
> >                 getdp at geuz.org <mailto:getdp at geuz.org>
> >                 http://www.geuz.org/mailman/listinfo/getdp <http://www.geuz.org/mailman/listinfo/getdp>
> >
> >
> >
> >
> >
> >
> >
> 

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://www.geuz.org/pipermail/getdp/attachments/20150810/a6a58d0e/attachment.html>