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<span style="color:rgb(32, 31, 30);font-family:"Segoe UI", "Segoe UI Web (West European)", "Segoe UI", -apple-system, system-ui, Roboto, "Helvetica Neue", sans-serif;font-size:15px;background-color:rgb(255, 255, 255);display:inline !important">Hi Lurii,</span></div>
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<span style="color:rgb(32, 31, 30);font-family:"Segoe UI", "Segoe UI Web (West European)", "Segoe UI", -apple-system, system-ui, Roboto, "Helvetica Neue", sans-serif;font-size:15px;background-color:rgb(255, 255, 255);display:inline !important"><br>
</span></div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
<span style="color:rgb(32, 31, 30);font-family:"Segoe UI", "Segoe UI Web (West European)", "Segoe UI", -apple-system, system-ui, Roboto, "Helvetica Neue", sans-serif;font-size:15px;background-color:rgb(255, 255, 255);display:inline !important">The issue might
also come from negative pressures in the EOS. Did you check that? I had the similar issues in the past while using some </span><span style="color: rgb(32, 31, 30); font-family: "Segoe UI", "Segoe UI Web (West European)", "Segoe UI", -apple-system, system-ui, Roboto, "Helvetica Neue", sans-serif; font-size: 15px;">SESAME
EOS tables. Those tables used </span><span data-markjs="true" class="markdmpdyndbt" data-ogac="" data-ogab="" data-ogsc="" data-ogsb="" style="font-size: 15px; font-family: "Segoe UI", "Segoe UI Web (West European)", "Segoe UI", -apple-system, system-ui, Roboto, "Helvetica Neue", sans-serif; color: rgb(32, 31, 30);">negative</span><span style="color: rgb(32, 31, 30); font-family: "Segoe UI", "Segoe UI Web (West European)", "Segoe UI", -apple-system, system-ui, Roboto, "Helvetica Neue", sans-serif; font-size: 15px;"> </span><span data-markjs="true" class="markanc8zzmso" data-ogac="" data-ogab="" data-ogsc="" data-ogsb="" style="font-size: 15px; font-family: "Segoe UI", "Segoe UI Web (West European)", "Segoe UI", -apple-system, system-ui, Roboto, "Helvetica Neue", sans-serif; color: rgb(32, 31, 30);">pressures</span><span style="color: rgb(32, 31, 30); font-family: "Segoe UI", "Segoe UI Web (West European)", "Segoe UI", -apple-system, system-ui, Roboto, "Helvetica Neue", sans-serif; font-size: 15px;"> to
emulate tension which is not ok with FLASH's solvers as it will make the thermal sound speed imaginary.</span></div>
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<span style="color: rgb(32, 31, 30); font-family: "Segoe UI", "Segoe UI Web (West European)", "Segoe UI", -apple-system, system-ui, Roboto, "Helvetica Neue", sans-serif; font-size: 15px;"><br>
</span></div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
<span style="color: rgb(32, 31, 30); font-family: "Segoe UI", "Segoe UI Web (West European)", "Segoe UI", -apple-system, system-ui, Roboto, "Helvetica Neue", sans-serif; font-size: 15px;">Thanks,</span></div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
<span style="color: rgb(32, 31, 30); font-family: "Segoe UI", "Segoe UI Web (West European)", "Segoe UI", -apple-system, system-ui, Roboto, "Helvetica Neue", sans-serif; font-size: 15px;">Nitish</span></div>
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<div id="divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" style="font-size:11pt" color="#000000"><b>From:</b> flash-users-bounces@flash.uchicago.edu <flash-users-bounces@flash.uchicago.edu> on behalf of kyv005@campus.mephi.ru <kyv005@campus.mephi.ru><br>
<b>Sent:</b> Thursday, April 1, 2021 1:47 PM<br>
<b>To:</b> flash-users@flash.uchicago.edu <flash-users@flash.uchicago.edu><br>
<b>Subject:</b> [EXT] [FLASH-USERS] Equation of state error</font>
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<div class="PlainText">Dear Flash users,<br>
<br>
I am trying to run a LaserSlab simulation for my own target material <br>
with the tabulated EoS.<br>
<br>
The simulation runs fine for some time, but at some point it starts <br>
throwing 'Eos: negative dE/dT is bad!' errors in the output file, and <br>
then it stops with the following message: 'DRIVER_ABORT: <br>
[hy_uhd_eigenParameters-A]: Zero or imaginary sound speed has obtained! <br>
Please try other (more diffusive) slope limiter, flux, order, cfl, etc.'<br>
<br>
I know the problem is with my EoS, since the same simulation runs <br>
without errors if I use the tables from FLASH. However, I cannot figure <br>
out what is wrong with my EoS - there should be no unphysical things <br>
that could possibly lead to negative sound speed and etc. in it. I have <br>
tried several of the suggested options (reducing cfl, changing slope <br>
limiters and etc.), but this did not solve the problem.<br>
<br>
So can you, please, help me determine what I might be doing wrong and <br>
how I can avoid these errors?<br>
<br>
Thank you in advance for your suggestions,<br>
<br>
Best regards,<br>
Iurii K.</div>
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