NORMAL particle in a GHOST cell

I have modified the conveyor-3d project. I set the solver to ‘Glued-sphere-particle’ and the Model of Solid 1 to ‘Glued-sphere particle DEM’. The Number of Spheres is set to 4.

I set the volume fraction to 0.05 to decrease the minimum required velocity to below 0.20.

I received the following error message:

‘Error: There exists a NORMAL particle in a GHOST cell. The particle may have gone OUT-OF-BOUNDS. To resolve this issue, please consider:
a) Verifying that all wall boundary conditions are defined.
b) Reducing the value of the variable NEIGHBOR_SEARCH_N (Solids>DEM>Maximum steps between neighbor search).
c) Increasing the particle and/or wall stiffness (Solids>DEM>Normal spring constant or Young’s modulus).
Current particle location (x, y, z coordinates): 0.7875, -2.581, 6.001
Current particle velocity (u, v, w components): -10.86, 21.78, 2.562.’

I attempted to increase the spring constant (from 10000 to 30000) and reduce the maximum steps between neighbor searches (from 25 to 15) in the Solids>GSP pane, but these adjustments have proven insufficient.

Please attach files! Thanks.

Thank you for your help in advance

conveyor_2024-05-02T174000.301881 (2).zip (2.5 MB)

I’m having trouble creating the bug report. MFIX exits while generating it, resulting in a zip file of 114 MB. However, after unzipping and then re-zipping it, the file size reduces to 2.5 MB. I’ve attached this smaller file to my previous post. Is this okay?

Thank you for following up. Based on your bug report, we have identified some issues with the GSP mass-inlet code and will be releasing a bug fix soon (this week, I hope). I wonder why the bug report failed? I have not seen that behavior before. Always something new!

– Charles

Thank you for your answer and for the bug fix in advance.

Hello, @cgw , I noticed a similar error message in a SQP test case, suggesting that issues may also be present within the SQP mass-inlet code. Kindly review the attached bug report file for further details. (7.3 MB)

I have downloaded MFiX 24.1.1. I have got the same error message as before."

This thread is continued at "NORMAL particle in a GHOST cell" in 24.1.1