Run diverged when simulating particle segregation using PIC method

MFiX Bug report
#1

Hi,

I am simulating the segregating process of two particle phases having large density difference. What is interesting i found is that by changing the sizes of particles, the simulations diverged at different flow times, which may be due to the segregation rate of different particle system. What’s more, when particles are not segregated, the simulation ran well. I am not sure that this issue is resulted from my settings or the possible bug in MFIX-PIC code. Can you please check it?

geometry.stl (3.5 MB)
geometry_0001.stl (3.5 MB)
mfix.dat (8.9 KB)

image
image1135×531 88.5 KB

Blended acceleration model
MFiX 22.2.1 is available for download
#2

Today i found that when the collision damping model was canceled, the simulation ran well.

#4

When two solid phases are set to be separated at initial, the method of cancelling the collision damping model is invalid. I tested the same case by using CPFD software. The result shows that CPFD has a better robustness.