CFDEM®coupling - User Forum

Hello everyone,

I am trying to use JKR model with CFDEM coupling model but I keep getting the following error:

Dear all, I have just installed the newest version of CFDEM 3.8.0 and can run the tutorial example successfully. However, when I am running a code of myself, I run into the error below. I attached my log file so that you may know how to fix this problem:

// run_parallel_cfdemSolverPiso_ErgunTestMPI_CFDDEM //

/home/Rachel/CFDEM/CFDEMcoupling-PUBLIC-5.x/tutorials/cfdemSolverPiso/ErgunTestMPI_1206/CFD

Dear all,

I have just installed the newest version of CFDEM (3.8.0) and have sucessfully run the example case in my computer (i.e ErgunTestMPI). However when I am trying to transfer the CFD results into VTK files, I use the command "foamToVTK" and get the error message as below:

---> FOAM FATAL IO ERROR:
wrong token type - expected scalar, found on line 5 the punctuation token ')'

I didn't change anything of this example and I don't know how to fix this problem, could anyone please give some clues? Thanks ahead!

Regards,
Rachel

Dear all,

I am doing a case study shown in tutorials of CFDEM and feel confused about "fix couple/cfd/force" and "fix couple/cfd/force/implicit" commands. The online documentation says the "fix couple/cfd/force" command contains contributions from all force models active in the CFD calculation, while the "fix couple/cfd/force/implicit" seems only contain the drag force coz it says "At every coupling time step the drag coefficient and the fluid velocity is transferred to LIGGGHTS".

I would like to install CFDEM (the latest version dated 27/11/2017) on Ubuntu 16.04 but when I use "cfdemCompLIG" command to compile LIGGGHTS, I get an error. I have installed OpenFOAM-3.0.1 (32 bit). I would appreciate any comments to resolve this issue. Please find below the error message I get:

An important aspect when using cfdemSolverPiso is that the particles must be smaller than the mesh cells in OpenFOAM.

In OpenFOAM one often does a pseudo-2D simulation where there is only one cell in Z-direction.

Hi everyone,

what would be the best way to carry out a one way couple simulation in which the particles "feel" the flow, but the flow is unafected by the particles?

Would setting alphamin to 1 achieve this correctly?

Hello,

Hi Everybody,

I am doing a CFDEM simulation of a microfluidic chip. On the OpenFOAM you have to use SI units. On the LIGGGHTS side you have choices. Since my microfluidic chip requires very small particles, I am working with micron units in the LIGGGHTs script.

Am I right believing the CFDEM-coupling assumes that we are working with SI units at all times? Checking the results in paraview it is obvious there is a big incongruence in the results from CFD and DEM. I imagine this arises from the code just tracking numbers and not the units, which he assumes to be SI.

Hi,
I've got a little issue with compilation on a new cluster (after everything has been running well with the old Uni cluster I was using, that is being decommissioned next month). I have compiled LIGGGHTS manually as a shared library, and it has created the liblmp_mpi.so in the LIGGGHTS /src directory, and i have the liggghts executable lmp_mpi. I compiled without VTK.