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Hi Antoine,
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<div class="">Regarding your first question, as far as I’m concerned, there’s no easy way to do so.</div>
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<div class="">For the second question, you can reduce the value of smlrho in your flash.par, which determines the minimum floor value for densities. Since your simulations are in physical units, I suggest you to check related parameters (e.g., smalle, smallt,
smallp) as well to make sure their values are appropriate.<br class="">
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Best regards,<br class="">
—<br class="">
Suoqing Ji<br class="">
Sherman Fairchild Fellow<br class="">
TAPIR & Walter Burke Institute for Theoretical Physics<br class="">
California Institute of Technology<br class="">
<a href="http://www.tapir.caltech.edu/~suoqing" class="">http://www.tapir.caltech.edu/~suoqing</a>
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<div class="">On Sep 18, 2020, at 2:16 AM, Antoine Gintrand <<a href="mailto:antoine.gintrand@gmail.com" class="">antoine.gintrand@gmail.com</a>> wrote:</div>
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<div class="">Dear flash users,</div>
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<div class="">I have two differents problems regarding FLASH,</div>
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<div class="">1) I would like to know if it is possible to ask FLASH (in the par file or somewhere else) to give plot output with less resolution than the check output. The problem is that I need big resolution for my simulation but it becomes difficult to
open them and analyse them in Visit and I would like to have output to analyse with less size than the data used for the real calculation.<br class="">
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<div class="">2) my second problem is that I am simulating two supersonic flows that collide in the interstellar medium (in 2D) where the initial conditions are two flows in opposite directions.</div>
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<div class="">The first fluid 1 in the left is defined with Density = 1.E-24, Velocity = 1.E10, Pressure = 1.E-5</div>
<div class="">The second fluid 2 in the right is defined with Density = 1.E-24, Velocity = 1.E10, Pressure = 1.E-7</div>
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<div class="">box size = 1.E13 * 1.E13 (all values are in CGS as FLASH convention)<br class="">
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<div class="">when I begin the simulation I have the following error :<br class="">
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<div class=""> INFO: Grid_fillGuardCells is ignoring masking.<br class="">
[ 09-18-2020 11:02:30.747 ] [mpi_amr_comm_setup]: buffer_dim_send=46871, buffer_dim_recv=46871<br class="">
[ 09-18-2020 11:02:30.805 ] WARNING after gc filling: min. unk(DENS_VAR)=0.9999999999999999237005E-24 PE=0 block=1 type=1<br class="">
[ 09-18-2020 11:02:30.883 ] WARNING after gc filling: min. unk(DENS_VAR)=0.9999999999999999237005E-24 PE=0 block=2 type=1<br class="">
[ 09-18-2020 11:02:30.977 ] WARNING after gc filling: min. unk(DENS_VAR)=0.9999999999999999237005E-24 PE=0 block=3 type=1<br class="">
[ 09-18-2020 11:02:30.997 ] WARNING after gc filling: min. unk(DENS_VAR)=0.9999999999999999237005E-24 PE=0 block=4 type=1</div>
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<div class="">I tried to change the initial conditions and it seems that the problem is that I cannot have initial densities below 1.E-10. But I need to simulate densities below these values in an astrophysical context. What can I do to solve this issue ?</div>
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<div class="">Thank you for your help,</div>
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<div class="">Best,</div>
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<div class="">Antoine Gintrand<br class="">
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