[Getdp] Resolution with a parameter

[Peter Kis]

Dear Christophe,

thank you for recommending me to look at the magnetodynamic problem. As I
see A-V formalism is used there and the Current_2D constraint is applied to
the electric scalar potential part i FunctionSpace  Hregion_u_Mag_2D.
However I don't have scalar potential in my particular problem. I use the
magnetic vector potential only.

Do you think it is possible to apply the same constraint to my problem too?

Best Regards

Peter


On Thu, Aug 13, 2015 at 6:26 PM, Christophe Geuzaine <cgeuzaine at ulg.ac.be>
wrote:

>
> You should simply impose the total current (including the induced
> currents) as a global quantity. See
>
>   http://www.geuz.org/getdp/doc/texinfo/getdp.html#Magnetodynamic-problem
>
> for a complete example (cf. the "Current_2D" constraint).
>
>
> > On 13 Aug 2015, at 16:47, Peter Kis <md2z34 at gmail.com> wrote:
> >
> > Dear Frederic,
> >
> > my final goal is to calculate the current (I = int_coil(js -
> sigma[]*Dt[{Aphi})) at every time instance and update the current density
> in order to achieve a certain current value.
> >
> > Regarding your suggestion, is it possible to define such constraint
> which depends on the solution (Aphi)?
> >
> > Best Regards
> >
> > Peter
> >
> > On Thu, Aug 13, 2015 at 4:40 PM, Frederic Trillaud Pighi <
> ftrillaudp at pumas.iingen.unam.mx> wrote:
> > Dear Peter,
> >
> > You may adjust your TimeFunction to your need in the constraint. It is
> interpolated during the resolution.
> >
> > Best,
> >
> > Frederic
> >
> >> On Aug 13, 2015, at 9:34 AM, Peter Kis <md2z34 at gmail.com> wrote:
> >>
> >> Dear List Members,
> >>
> >> I'm just wondering if it's possible to scale the current density from
> the time iteration loop.
> >>
> >> Here I introduced a parameter current_factor,
> >>
> >> Function{
> >>     ......
> >>     current_factor = 1.;
> >> }
> >>
> >> which appears in the formulation as a scaling factor for the current
> density:
> >>
> >> Formulation{ // OK
> >>   {Name VectorPotentialFormulation; Type FemEquation;
> >>    Quantity{
> >>      {Name Aphi; Type Local; NameOfSpace Afs;}
> >>      {Name js; Type Local; NameOfSpace jfs;}
> >>    }
> >>    Equation{
> >>     Galerkin{ [1/mu0*Dof{Curl Aphi},{Curl Aphi}];
> >>       In Omega; Jacobian JVol; Integration I1;}
> >>
> >>     Galerkin{ DtDof[sigma[]*Dof{Aphi},{Aphi}];
> >>       In Omega; Jacobian JVol; Integration I1;}
> >>
> >>     Galerkin{ [-current_factor*Dof{js},{Aphi}];
> >>       In Omega_coil; Jacobian JVol; Integration I1;}
> >>     }
> >>   }
> >> }
> >>
> >> and I'd like to update this parameter during the time iteration:
> >>
> >> Resolution{
> >>   {Name Solution;
> >>     System{
> >>       {Name Syst; NameOfFormulation VectorPotentialFormulation;}
> >>     }
> >>     Operation{
> >>         InitSolution[Syst];SaveSolution[Syst];
> >>         TimeLoopTheta[t0,tmax,dt,theta] {
> >>             current_factor = 1/1.7;  // This has no effect!!
> >>             Generate[Syst]; Solve[Syst]; SaveSolution[Syst];
> >>         }
> >>     }
> >>   }
> >> }
> >>
> >> but this has no impact on the solution. Apparently the value of
> current_vector is still considered one as it's defined in Functions.
> >>
> >> Is there any way to update this parameter from the time loop?
> >>
> >> Thanks for your help in advance.
> >>
> >>
> >> Peter
> >>
> >> _______________________________________________
> >> getdp mailing list
> >> getdp at geuz.org
> >> http://www.geuz.org/mailman/listinfo/getdp
> >
> >
> > _______________________________________________
> > getdp mailing list
> > getdp at geuz.org
> > http://www.geuz.org/mailman/listinfo/getdp
>
> --
> Prof. Christophe Geuzaine
> University of Liege, Electrical Engineering and Computer Science
> http://www.montefiore.ulg.ac.be/~geuzaine
>
>
>
>
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