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<p>Dear all,<br>
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<p><br>
</p>
<p>I forgot to include the log file.<br>
</p>
<p>Unfortunately, I neglected to save the log file for this run.<br>
</p>
<p>However, I do have a log file from a previous simulation in the same setup.<br>
</p>
<p>The only difference is that I ran it with a different temperature, but the results were largely the same.<br>
</p>
<p><br>
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<p>- Michiel<br>
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<div id="divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" color="#000000" style="font-size:11pt"><b>From:</b> flash-users-bounces@flash.uchicago.edu <flash-users-bounces@flash.uchicago.edu> on behalf of Michiel Bustraan <michiel.bustraan@astro.su.se><br>
<b>Sent:</b> Wednesday, March 22, 2017 2:10 PM<br>
<b>To:</b> flash-users@flash.uchicago.edu<br>
<b>Subject:</b> [FLASH-USERS] Numerical Effects in Spherical Coordinates</font>
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<p>Dear FLASH Users,<br>
</p>
<p><br>
</p>
<p>I've been running 2D simulations of shocks in spherical simulations.<br>
</p>
<p>The initial conditions involve a high density around the origin.<br>
</p>
<p><br>
</p>
<p>I had to introduce random temperature fluctuations in the inner region to ensure refinement.<br>
</p>
<p>I started with quite a high level of refinement, and the maximum level of refinement decreases over time (from 10 layers to 5).<br>
</p>
<p><br>
</p>
<p>I've found that ripples appear in the inner portion of the domain, as well as larger numerical artifacts.<br>
</p>
<p>I think that these might either be due to:<br>
</p>
<p><br>
</p>
<p>- The initial temperature fluctuations I added, though I feel these would be too small (spatially) to cause all these issues.<br>
</p>
<p>- Could it be that the higher pressure region in the center, combined with the lower radial velocity, cause the gas to bounce off the inner boundary?<br>
</p>
<p>This might create ripples and internal shocks.<br>
</p>
<p><br>
</p>
<p>Either way, I'm not certain how to improve my results from here.<br>
</p>
<p>If anyone has had similar problems, I would greatly appreciate some advice.<br>
</p>
<p><br>
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<p>The figures attached highlight my problem.<br>
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<p><br>
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<p>Kind Regards,<br>
</p>
<p>Michiel Bustraan<br>
</p>
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