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<p class="MsoNormal">Dear getDP-users,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I am currently struggling with simulating Eddy Current Testing in getDP. I have implemented a simplified model (one turn as an excitation coil with sinusoidal source current and a metal sheet as test specimen). I use an A-V-formulation
(magnetic vector potential and electric scalar potential). I use a theta-time scheme for the time-varying source current in the coil. My current .geo and .pro-files are in the appendix. The magnetic field of the coil is calculated correctly in time, however
the eddy current induced in the conductor result into zero and I don’t have an explanation for that. Further, the magnetic vector potential doesn’t change in time and the electric potential is not defined in all volume elements of the air. I would be very
pleased if someone could help me with these issues. Here are some remarks concerning my implementation:<o:p></o:p></p>
<p class="MsoListParagraph" style="text-indent:-.25in;mso-list:l0 level1 lfo1"><![if !supportLists]><span style="mso-list:Ignore">-<span style="font:7.0pt "Times New Roman"">
</span></span><![endif]>The fifth integral term in the Formulation constraints the gradient of the electric potential at the surface of the conductor. Because I didn’t know how to implement this as a constraint, I put this term in the formulation and use a
user-defined function for the normal component. Is this ok?<o:p></o:p></p>
<p class="MsoListParagraph" style="text-indent:-.25in;mso-list:l0 level1 lfo1"><![if !supportLists]><span style="mso-list:Ignore">-<span style="font:7.0pt "Times New Roman"">
</span></span><![endif]>I set the electric potential in a randomly chosen point to zero to ensure the solution is unique.<o:p></o:p></p>
<p class="MsoListParagraph" style="text-indent:-.25in;mso-list:l0 level1 lfo1"><![if !supportLists]><span style="mso-list:Ignore">-<span style="font:7.0pt "Times New Roman"">
</span></span><![endif]>I also noticed that the magnetic field in the conductor is relatively high and does not change in time.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Because I am quite new to getDP...is there any paper or similar that describes finite element calculations with eddy currents?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Thank you very much in advance,<o:p></o:p></p>
<p class="MsoNormal">Judith.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><span lang="DE">--------------------------------------------<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="DE">M.Sc. Judith Mengelkamp<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="DE"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="DE">Technische Universität Ilmenau<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="DE">Institut für Biomedizinische Technik und Informatik (Institute for Biomedical Engineering and Informatics)<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="DE">Fachgebiet Biomedizinische Technik (Biomedical Engineering Group)<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="DE"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="DE">Phone: +49 3677 69-1958<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="DE">Fax: +49 3677 69-1311<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="DE">e-mail: judith.mengelkamp@tu-ilmenau.de<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="DE"><o:p> </o:p></span></p>
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