Fluidized bed with internal baffles--Negative void fraction detected and DT < DT_MIN

Hi MFIXers, I tried to simulate a fluidized bed with internal baffles using TFM model. The geometry is generated in Solidworks. I used MFIX to do the meshing and build up the model.

However, I always got the error “Negative void fraction detected” and “DT<DT_MIN”. I would very appreciate if you could help me check my .mfx file and point out the potential errors. Thank you!
case33_2023-03-28T144701.294100.zip (1.4 MB)

Your stl file was not included, so I used geometry.stl instead. Maybe your STL normals are pointing in the wrong direction, please check and attach the stl file.

https://mfix.netl.doe.gov/doc/mfix/22.4/html/faq.html#how-to-verify-flip-stl-file-facet-normals

Hi Jeff, here is my .stl file. I think the STL normals are fine.
case2.STL (60.6 KB)

Hi Jeff, I am sorry to interrupt you. Do you receive the .stl file? I have checked the normals and they ar fine. I have bothered by this error in this simulation case for a while. Would you please help with checking .mfx and .stl files? Thanks!

Yes I see the STL file but I have not had a chance to take a look. Thank you for your patience. MFiX users are encouraged to help each other too.

Hi lyang88, The code complained that the solids pressure (P1) doesn’t converge, so changed the solids viscous stress model to Lun, made the grid in the y direction finer, the code can run without problem to about 0.1s. Please check if it works for you for a longer simulation time.
For_Lei.zip (62.9 MB)

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Hi Yupeng, thanks for your kind help! I think it can work now.