[FLASH-USERS] Negative 3T Internal Energy when including Nernst

[Rover, Edoardo]

Dear FLASH users,

I am attempting to implement extended-MHD in my simulation, and started by enabling the Nernst term in the simulation. However, I get a "Negative 3T Internal Energy" error. Following a previous user email, I attempted to enable the flux limiter options for Nernst, and set them to:
nernstFlMode = "fl_minmax"
nernstFlCoef = 0.08
But the error presented itself once more. I previously attempted to use the "fl_larsen" option as well, and set the flux limiter to "0.09", the same value we are using for the electron conduction flux limiter, but the problem persists.

Setting "use_Nernst" to ".false." makes the simulation run without problems. Preheating the materials or changing the diffusion dt factor (or the radiation transport one) shows no changes, the simulation runs normally if Nernst is set to False, while it crashes if set to True.

For that reason, I think the issue lies entirely in the MHD setup block. Would you have any suggestions on the issue?

Best regards,

Edoardo Rovere

Postdoctoral researcher
UCSD CER
3183 Matthews Ln 92093
La Jolla (CA), US
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