CFDEM®coupling - User Forum

Hello All

I have tried to install the CFDEM coupling along with the software packages OpenFoam and LIGGGHTS in my Ubuntu system (Ubuntu 20.04.1 LTS on virtual machine). I am following the instruction from the CFDEM website (https://www.cfdem.com/media/CFDEM/docu/CFDEMcoupling_Manual.html#install-3). But when OpenFoam is downloaded from git (recommended version OpenFOAM-5.x) and compiled by adding the following lines in .bashrc and running the ./Allwmake.

Hello,
Does anyone have a picture or figure that shows how the spheres are divided.
I tried doing this and I am getting spheres that overlap.
I have attached some python code (will need numpy) that recreates the structure.
Does anyone know where I could find more literature about this method?
Below is what I found for the x,y,z locations and r is set to sqrt(1/29) for each sphere.

Thank you for any and all help.

Dear all,

I have compiled the latest version of LIGGGHTS 3.8.1 and CFDEMcoupling 3.8.0 together with OpenFOAM 5.x on our cluster as well on one of the local workstations. The programs were used together with following software versions of g++, gcc and MPI:

- g++ (GCC) 8.4.0
- gcc (GCC) 8.4.0
- mpirun: (Open MPI) 2.1.6

Hello All, when i input command "reconstructPar", the output says that "cannot find file twoShpereGlowinskiMPI/CFD/processor0/0.003/ployMesh/pointProAddressing"

Could someone please help me solve or explain this problem?

Thank you,

Hello liggghts forum, I am trying to run a simple simulation after following an example which is available in liggghts. I am just dropping single particles on by one on the region. Some how I did this simulations after changing 'boundary m m m'. But the problem is that particles are dropping outside of my mesh domain.

I have included my script here.
mesh that I am using is from example of liggghts calles 'simple_chute.stl'.

********script*******

Dear all,

I'd like to set a fixed temperature condition at the inlet and outlet. I found "run XX every XX " " " should be used to keep the temperature constant during the simulation. However, the CFDEM coupling liggghtsCommands can not recognize the quotation mark.

#run to see heat transfer
run 100000 every 1 "set region top_outlet property/atom Temp 200." "set region bottom_inlet property/atom Temp 300."

Dear all,

I am simulating the heat transfer aiming to calculate the effective thermal conductivity of a sphere packing.

I started by modifying the example "cfdemSolverPisoScalar/packedBedTemp" and have the following questions.

1. Why are both in.liggghts_init and in.liggghts_run required in DEM folder?
ParDEMrun.sh calls "in.liggghts_init" but I got error if I delete in.liggghts_run.
Which file calls "in.liggghts_run"? and why is "run 0" defined in "in.liggghts_run"?

Hello All, the output file from a CFDEM simulation says that

"Reading voidfraction field voidfraction = (Vgas/Vparticle)".

Is it not that void fraction is Vgas/Vcomputationalcell?

Thank you,
Jagan Mohan.

I am using Liggghts-Public with cfdem coupling version 3.8 to simulate a triaxial test.

I saved the state of my first simulation with write_restart in order to reload it in another simulation

On loading the binary restart file into the new simulation, i got this error:
"Pair granular with shear history requires newton pair off"

I checked from the error section of the documentation the information i got was:
"This is a current restriction of the implementation of pair granular styles with history."

Hi everyone

I try to use dump custom fx fy fz f_dragforce(1) f_dragforce(2) f_dragforce(3) to record the total forces and fluid drag forces on each particle.