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<p class="MsoNormal">Hello everyone,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><span lang="EN-US">I am writing here to seek possible help on how to implement variable material properties for simulation of a superconductor. To give some context, I am interested in the magnetodynamical simulation of superconducting
devices in the time domain. As you can see in the enclosed files, I use an H-Phi formulation based originally based on the helix.pro example. In it, the superconductor properties were modelled by a power law
<b>E</b>(<b>J</b>) = ( E<sub>0</sub> / J<sub>c</sub> ) * (|<b>J</b>| / J<sub>c</sub> )<sup>N-1</sup> *
<b>J</b>. This is ok, but to better describe the material I want to use values of J<sub>c</sub> and N that are not constant anymore and depend on the magnetic field H. I have available experimental data for J<sub>c</sub> and N at different field level and for
different orientations, my idea was thus to plug them into the power-law via the interpolation functions GetDP already has.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">This is what I have done in the enclosed files, yet in a way that does not fully satisfies me. Namely, I use for each time step the J<sub>c</sub> and N values computed based on H at the previous time iteration. Given
what has been done by Christophe in the original helix.pro example, I would expect that one can implement a dEdH[{h}, {d h}] function to replace his dEdJ[{d h}] and take into account the value of H at the current time step, i.e. Dof{d h}. However, calculating
this function looks horrific and I would really like to make sure this is the right way to go before I do anything. This is why I am here : is there any alternative that I would not have thought of ? Thank you in advance for your help,<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Sincerely Yours, <o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Tahoma",sans-serif;color:#000099;mso-fareast-language:FR">Guillaume DILASSER</span><span style="font-size:10.0pt;font-family:"Tahoma",sans-serif;color:#000099;mso-fareast-language:FR"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:7.5pt;font-family:"Arial",sans-serif;color:#000099;mso-fareast-language:FR">Doctorant SACM / LEAS<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:7.5pt;font-family:"Arial",sans-serif;color:#000099;mso-fareast-language:FR">CEA - Centre de Saclay - Bāt.123 - PC 319c</span><span style="color:#000099;mso-fareast-language:FR"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:7.5pt;font-family:"Arial",sans-serif;color:#000099;mso-fareast-language:FR">91191 Gif sur Yvette Cedex - France -</span><span style="color:#000099;mso-fareast-language:FR"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:7.5pt;font-family:"Arial",sans-serif;color:#000099;mso-fareast-language:FR"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:7.5pt;font-family:"Arial",sans-serif;color:#000099;mso-fareast-language:FR"><a href="mailto:guillaume.dilasser@cea.fr"><span style="color:blue">guillaume.dilasser@cea.fr</span></a><o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
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