[FLASH-USERS] The problem of Negative Internal Energy in 3T MHD simulation with laser generated plasmas

[Huo Wenyi]

Dear all:

I am using FLASH to simulate the magnetohydrodynamics in  laser generated plasmas. However, I always encounter a problem of negative internal energy both in FLASH 4.5 and FLASH4.6. Does anyone encounter such a similar problem?  The error information in the Log file is as follows:


[ 04-16-2019  14:34:35.488 ] [hy_uhd_ragelike] ERROR DETECTED
[ 04-16-2019  14:34:35.488 ]   Zero or negative advected specific internal energy detected
[ 04-16-2019  14:34:35.488 ]   DENS_OLD =  1.0000904290291E-09
[ 04-16-2019  14:34:35.488 ]   DENS_NEW =  1.0000983091349E-09
[ 04-16-2019  14:34:35.488 ]   UTOT_NEW = -3.7386802822434E-01
[ 04-16-2019  14:34:35.488 ]   UEXTRA = -1.7491864582091E+01
[ 04-16-2019  14:34:35.488 ]     UELE_NEW = -3.7135596091566E-01
[ 04-16-2019  14:34:35.488 ]     UION_NEW = -2.5120492887951E-03
[ 04-16-2019  14:34:35.488 ]     URAD_NEW = -1.8019885718467E-08
[ 04-16-2019  14:34:35.488 ]     EELE_VAR =  1.7001438966846E+10
[ 04-16-2019  14:34:35.488 ]     EION_VAR =  1.1498940630502E+08
[ 04-16-2019  14:34:35.488 ]     ERAD_VAR =  8.2498749422145E+02
[ 04-16-2019  14:34:35.488 ]     EELE     = -3.7131945682109E+08
[ 04-16-2019  14:34:35.488 ]     EION     = -2.5118023556785E+06
[ 04-16-2019  14:34:35.488 ]     ERAD     = -1.8018114373230E+01
[ 04-16-2019  14:34:35.488 ]     uele_adv  =  1.7002978536045E+01
[ 04-16-2019  14:34:35.488 ]     uion_adv  =  1.1501719275908E-01
[ 04-16-2019  14:34:35.488 ]     urad_adv  =  8.2506210304961E-07
[ 04-16-2019  14:34:35.488 ]   PELE_VAR =  1.2145270532940E+00
[ 04-16-2019  14:34:35.488 ]   PION_VAR =  7.6660475248193E-02
[ 04-16-2019  14:34:35.488 ]   PRAD_VAR =  2.7502069901319E-07
[ 04-16-2019  14:34:35.488 ]   PELE_ADV =  1.2145343502140E+00
[ 04-16-2019  14:34:35.488 ]   PION_ADV =  7.6672066071296E-02
[ 04-16-2019  14:34:35.488 ]   PRAD_ADV =  2.7502070101654E-07
[ 04-16-2019  14:34:35.488 ]   TELE_VAR =  6.0996867323016E+02
[ 04-16-2019  14:34:35.488 ]   TION_VAR =  3.6907447766733E+00
[ 04-16-2019  14:34:35.489 ]   TRAD_VAR =  1.0219015193890E+02
[ 04-16-2019  14:34:35.489 ]   CELL X =  3.3222656250000E-01
[ 04-16-2019  14:34:35.489 ]   CELL Y =  6.9890625000000E-01
[ 04-16-2019  14:34:35.489 ]   CELL Z =  0.0000000000000E+00
[ 04-16-2019  14:34:35.489 ]   You might be able to get things to keep running by trying
[ 04-16-2019  14:34:35.489 ]   more diffusive hydro options (reduce CFL, order, etc...)
[ 04-16-2019  22:00:17.496 ] [hy_uhd_ragelike] Negative internal energies in 3T update
[ 04-16-2019  22:00:17.496 ]   Falling back to using internal energy ratios instead of pressure ratios




I have tried many different RiemannSolvers. It does not help. I guess that this problem is related to the grid size, but I am not sure.

Can anyone provide a solution to this problem? Thank you very much!

Best regards,

Wenyi Huo

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://flash.rochester.edu/pipermail/flash-users/attachments/20190417/a66bdae6/attachment.htm>