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<p class="MsoNormal"><span style="font-size:11.0pt">Hi Wang,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">Have you plotted the species variables (fill, line, vacu) to make sure you still have vacuum in the domain? It would also be good to check the resistivity (res2).<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">It¡¯s hard to tell what might be going wrong without more info. Can you send the par file?<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;color:black">--</span><span style="color:black"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Arial",sans-serif;color:#181A1B">Eddie Hansen</span><span style="color:black"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Arial",sans-serif;color:#181A1B">Research Scientist</span><span style="color:black"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Arial",sans-serif;color:#181A1B">Flash Center for Computational Science</span><span style="color:black"><o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
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<p class="MsoNormal" style="margin-bottom:12.0pt"><b><span style="font-size:12.0pt;color:black">From:
</span></b><span style="font-size:12.0pt;color:black">flash-users <flash-users-bounces@flash.rochester.edu> on behalf of
</span><span style="font-size:12.0pt;font-family:"MS Gothic";color:black">Íõ</span><span style="font-size:12.0pt;font-family:"PingFang TC",sans-serif;color:black">¶«</span><span style="font-size:12.0pt;font-family:"MS Gothic";color:black">Éý</span><span style="font-size:12.0pt;color:black">
<wangdswork@stu.xjtu.edu.cn><br>
<b>Date: </b>Thursday, April 27, 2023 at 1:19 PM<br>
<b>To: </b>flash-users <flash-users@flash.rochester.edu><br>
<b>Subject: </b>[FLASH-USERS] Diffusion problem of angular magnetic field in one dimension<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt">Dear FLASH user & developers,<br>
I have a question about implicit magnetic diffusion in FLASH4.7. I wanted to observe the diffusion of angular magnetic field in one dimension, so I set the fluid velocity to zero in the "Simulation_adjustEvolution.F90" file to rule out the magnetic freezing
effect. However, I found that the magnetic field diffused slowly in vacuum, which is quite different from the result of a paper I saw. I have attached the comparison diagram of the two results.
<br>
The vacuum resistivity I set is 1e9(cm2/s), and the vacuum region is between 0.8 and 1cm. I modified it on the Z-Pinch file, and the current was set to 1MA.<br>
I would appreciate any help.<br>
Thanks!<br>
Best,<br>
Wang Dongsheng<o:p></o:p></span></p>
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