CFDEM®coupling - User Forum

Hi ,
I am working on carbon particles in order to use them as the slurry flow in the battery. The size of the carbon particle is between 1 to 10 Micrometer and they will place in water in a microchannel.
Considering that a part of my studies before doing my experimental investigation is a numerical simulation, I've decided to simulate the behavior of particles and the effects of fluid flow on charge and discharge of the battery.

Dear all, I have a really basic question regarding the settlingTestMPI tutorial. As far as I understand it simulates the settling of a sphere in a still fluid and compares the simulation results with the analytical Stokes (creeping flow) solution. But I can't find a reference (paper) of the expressions used in the .m scrip. I understand that It performs and explicit integration of the position but I cannot find a reference of the velocity determination.

I've attached bellow the octave script.

Cheers,
Mauro

Dear CFDEM users,
I am running a case in which an STL file as a gate moves up a specific distance and after it stops. So I need to use restart CFDEM.
However, I faced with this error:
Mesh elements have been lost / left the domain. Please use 'boundary m m m' or scale/translate/rotate the mesh or change its dynamics
I modified liggghs command and coupling properties like Erugan_resatart but I do not know why the gate does not stop.
I would be thankful if you help me to solve it.
Best,
Shadi

Dear CFDEM users,
I am working on a case in which I need to use restart CFDEM.
In the case I need to move up a STL file and stop it and running the case with the stoped STL file.
So I did :
First, loading the particles(liggght-init)
Second, using an STL file as a gate which moving up till t=0.05(liggghts_run)
Last, running the case without the gate. (liggghts_restart)
I have a question regarding the controlDict which controls the running time.

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?