Particle-Output file does not contain all particles

MFiX Bug report
#1

Hello,

I would like to report a possible bug. Namely, I used version 23.1.1 to simulate a fluidized bed. However, not all particles are written to the particle output file, but only a fraction of them. So in my case for example instead of 400000 particles there are only approximately 158000 particles in the output file. Is this bug already known? In earlier versions this does not occur.

With best regards

Fritzi
BFB_Large_ParticleSetl200.mfx (10.5 KB)
calc_force_dem.f (15.4 KB)
calc_collision_wall_mod.f (42.4 KB)

#2

Please attach your project so we can have a look

#3

I now edited my post and attached the mfix-file and my user-defined-functions.

#4

Hi Fritzi, thanks for the speedy response.
I am able to reproduce this error.
I ran your case out to a stop time of 0.001 s and at that time, we get a message

Number of particles in the system                 =    406926
Number of particles left after filtering the data =    406926

The particle_output.dat file says

Dimension:    3                               
Particles:    406926

but the file only has 211049 lines.

I am looking into this now, will follow up here when we know more.

#5

A bug in MFiX is causing the solver to exit prematurely in some cases, before all output files are written. We will be releasing version 23.2 soon, which will remedy this problem. Thanks for the report, and sorry for the trouble!

#6

Thank you very much for your response.

#7

Note that MFiX version 23.2 was just released and remedies the problem you reported.
We rely on feedback from our users to keep improving MFiX.
Thank you for the bug report and sorry for any trouble!