[FLASH-USERS] Negative 3T Internal Energies

[Rodger, Izzy]

Good morning!

I'm trying to run the LasSlab example using equation of state tables in the sesame format, however an error message that I'm encountering often is:


[hy_uhd_eigenParameters-A]: Zero or imaginary sound speed has obtained! Please

 try other (more diffusive) slope limiter, flux, order, cfl, etc.

The position of this error in the simulation seems to be at different points along the target-chamber boundary.

A forum post from 2019 recommended lowering the cfl, and when I did this (lowered it from 0.8 to 0.01) I was able to run the simulation and receive a reasonable output - but the runtime is very long. I do not receive the error when I use the pre-packaged ionmix4 file for aluminium, and it runs in a much better time. Perhaps it is a problem with my EOS table?

Does anybody have any ideas for what else I could do to try and resolve this issue without sacrificing simulation runtime?

Kind regards,
Izzy
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