CFDEM®coupling - User Forum

Hi Everyone,

Does anybody have some references for the added mass coeffient in the gradP and viscous force models?

Or is this left over from the versions which did not include a separate virtual mass force model?

Regards

Victor

Hi Everyone,

Could someone tell me how I can set the particleCloud_.cg value for an entire simulation?

Thanks,

Victor

Hello to everyone.
I have been trying to modify the twoSpheresGlowinski tutorial from CFDEM in order to simulate a coupled flow (sedimentation) of particles (~400μm diameter) into a non Newtonian fluid.
My main problem seams to be that no cells are selected to be refined and Courant number increases as the steps progress.
These is the log output of the 7th step where it cruses.

Selected 0 cells for refinement out of 8000.
Selected 0 split points out of a possible 0.
Courant Number mean: 1.78356e+41 max: 2.46448e+43

What do I have to change???

Dear all,

I have some doubt about how to set the "KochHillDrag" model.
My case treats a cloud of solid particles that flows through a high viscosity liquid.
I found that the simulation blows up due to the drag force values, which arise almost immediately.
On the other side I found that, setting the "scaleDrag" parameter to a value much lower than 1 (between 0.3 and 0.5),
the simulation becomes stable and runs well.

Hello!

Hello All,

I was wondering where I can get examples for liggghts version 3.30. Examples in the following link are not working:
https://github.com/CFDEMproject/LIGGGHTS-PUBLIC/tree/master/examples/LIG....

thanks for your help

Hi all!

I want to simulate a case in which I just want to consider temperature coupling between fluid and particles using LaEuScalarTemp. Is there a possibility to switch off the calculation of forces and momentum exchange completely?

Dear all,

I would like to submit to your attention an annoying problem I am not not able to solve.

Hi,

I am running into memory issues running cfdem on a cluster. I wanted to know if there is a way to estimate memory requirement of a simulation.

My current case is an 18" sphere with one inlet on side and one outlet on top. I was wandering if the size of the sphere could influence the memory requirements of the simulation and if yes then how. Is there any method to find an estimate of memory requirements?
If my simulation asks for more memory than what is defined on the cluster then it will crash and stop.

Thanks,
Mohsen

Dear all,

I am running the CFDEMsolverIB tutorial and I want to visualize my CFD and DEM results in paraview. To visualize this I obtained VTK files via adding reconstructCase="true" to the parCFDEMrun script & command and as I am running on multiple processors I had to add the "reconstructParmesh" command to the parCFDEMrun function.

Now when running the simulation I fall into the following error:

--> FOAM FATAL ERROR:
cell, tetFace and tetPt search failure at position (-0.00079004318 -0.001127873 0.0044064325)
for requested cell 0