CFDEM®coupling - User Forum

Hi,everyone
I have several problems compiling CFDEM. I have tried my best but I can not deal with it...

Backgroud:
1. Because of some reason, I have to compile CFDEM with old version. (CFDEMcoupling 3.0.1, LIGGGHTS 3.5.0 and OpenFoam 3.0.1)
2. I think LIGGGHTS and OpenFoam have been already compiled correctly.
3. The error occured in the step "cfdemCompCFDEMall"

Problem:
At first, I found error in the logfile "log_complog_compileCFDEMcoupling_cfdemSolverPiso". The detail is shown below:

Hi,

I am trying to model liquid and particle flow inside a tank generated due to the rotation of a stirrer inside the tank. The stirrer is rigid and rotates at a constant angular velocity. I need to use dynamic mesh to implement the motion of the stirrer. I am not sure how to implement dynamic mesh in CFDEM-coupling. Can anyone suggest me how to implement dynamic mesh in CFDEM-coupling? Please also let me know if there is any tutorial on dynamic mesh in CFDEM-coupling

Thank you.

with regards,
Hossain

Hi all,

I am new to CFD-DEM area. I want to run the tutorials for ErgunTestMPI. But I got the error:
----------------------------------------------------------------------------------------------------------------------------------------------------
// run_parallel_cfdemSolverPiso_ErgunTestMPI_CFDDEM //

/home/caocd/CFDEM/caocd-PUBLIC-7/run/ErgunTestMPI/CFD

Hi,
I found the calculation of the normal relative velocity did not contain the rotation velocity contribution, which is no consistent with the literature formula.
In surface_model_default.h
// relative translational velocity
const double vr1 = sidata.v_i[0] - sidata.v_j[0];
const double vr2 = sidata.v_i[1] - sidata.v_j[1];
const double vr3 = sidata.v_i[2] - sidata.v_j[2];

Hello Users,

I am trying to solve pneumatic conveying system with dense solid flow regime (void fraction varies from 1 to 0.35), using CFDEM two-way coupled solver. The versions are OpenFoam 5.0 and LIGGGHTS-Public 3.8.0.

Hi,
I want to insert particles at fixed points while CFD is running. I tried using execute in liggghtsCommands for create_atoms with startTime and endTime. But even with the runEveryCouplingStep off, LIGGGHTS creates atoms at each coupling step. How should I create only one atom at t=0.0001s for instance?

DearCFDEM user,
I want to see the CFDEM simulation results in ParaView. But the problem is that it does not show CFD and DEM results at the same time. The particles movement are shown later.
I would be thankful if you could help me.
Best,
Shadi

Dear CFDEM users,
I do not know why when I change the number of particles in CFDEM cases the results do not change in the Paraview.
I think it shows the previous results whereas the number of particles has been changed.
I would be thankful if you could help me to solve this problem.
Best,
Shadi

Hi,

I need to insert particles randomly, or at fixed points, in a limited number and at a very low rate (CFDEM case). I am currently using fix insert/rate/region command. Although it is to insert particles randomly, they are inserted too close to the center of the defined region. How can I insert particles in the whole region? (It is not because of the processor boundary. I use overlapcheck no.)

Hello everyone !

I have adapted "pair_style_colloid" and "pair_style_yukawa/colloid" from LAMMPS into LIGGGHTS (v3.8.0). The implementation works fine. I just want to know is it possible or does LIGGGHTS also calculates the interaction energy ?

I have gone through LIGGGHTS documentation and found some hints like using compute group/group command,
https://www.cfdem.com/media/DEM/docu/compute_group_group.html