Paricle_input.dat file with automatic particle generation

MFiX
1

Hello,

I had two inquiries about setting up DEM cases.

  1. I have been using the particle_input.dat file for specifying DEM particle positions in my domain. Along with that, I was thinking of using particle automatic generation from a boundary for my case. Can this be done in any way? All I found is that if I turn on the automatic particle generation option, it will overwrite my particle_input.dat file, as particle information from the .dat file won’t be taken in the case. Is there any way to use both of these together?
  2. I am running a pure DEM case by disabling the fluid solver. I am using the particle_input.dat file to specify particle locations and the diameter of the particles. In the GUI, there is an option in the solid pane to specify my solid phase diameter. If the value of the diameter in the .dat file and the solid pane are different, will it create any issues for pure DEM simulations?

I hope to receive the answers. Thank you.

2

First, we encourage users to switch to the newer particle_input.csv instead of the old particle_input.dat format.

  1. This is not supported, it is either one method, not both. You would need to spend some time studying the code and implement this yourself. This is tricky because you need to make sure there is no overlap between particles generated from the automatic generation and the particle_input file.
  2. This could be an issue since the des grid size and solids time steps are based on the particle size. It is best to keep values consistent. With the newer csv file format, if the diameter is constant, you can remove the diameter column from the csv file to avoid this potential issue.