Information about MFiX warnings and EPgErr.log file

[KAMAL_KISHOR_PANDEY]

Hello @jeff.dietiker . I am new to MFiX. I am trying to simulate a 2D bi-disperse gas-solid fluidized bed. During simulation, I get this warning :
Velocity exceeds limit : _ in cell _

I find this in the EPgErr.log file :
One or more cells have reported a negative gas volume fraction (EP_g)
and negative void fraction detected in the log file.

I just want to know whether I can trust my simulation results by simply ignoring these errors and warnings or will i have to re-run the simulation ?. I am attaching herewith the .mfx file
2d_TFM_finemesh_bidisperse_LBST_0.13175.mfx (11.0 KB)

Please let me know whether i can proceed or not. Your help would be much appreciated. Thanks.

[jeff.dietiker]

It is usually fine to get unphysical values and divergence along the run. When this occurs, the time step decreases and MFiX goes back to the previous time step and iterates again until convergence is achieved. Unless you see the time step go down significantly and not being able to go back up over time, or you see abnormal hydrodynamics behavior, I would say it is safe to proceed. It is ultimately your responsibility to assess the value of the simulation results.