CFDEM®coupling - User Forum

Hi,

I am using all the files from a previous simulation of OpenFOAM in the start time folder of a CFDEM case.
The problem I am facing is that the uniform folder which is required to preserve previous RMS data is being overwritten by CFDEM solver and subsequently further RMS values are also incorrect. Can anyone please suggest ho to avoid this overwriting uniform folder?
channelFoam solver was not making these changes in the uniform folder.

I tried to work with diameter of particle about 20-100 microns, but I read here there are a limit because a precision machine issue and just I could work with 124 microns of diameter min in SI units. I changed my problem to CGS units, but I have some questions. In the example of tutorial ErgunTestMPI_cgs, the script Allrun.sh calls to controlDict_cgs_2.2.x and copy in other directory. It is necessary? What is it doing exactly ? .

Hello everyone,

I have been trying to install cfdem in the past few days but I have had little success.

I am running Ubuntu 13.04. I already had OpenFOAM installed and I have been using extensively, so this should not be a problem. I have installed Ubuntu using the deb pack online using this procedure :
http://www.openfoam.org/download/ubuntu.php

I have installed LIGGGHTS and LPP and have been able to run the test cases without any problem and visualize the results.

Hi Chris,

I am a bit curious about the term "explicit force" (i.e. expParticleForces in paraview).

When using Model A, the governing equation is referred to Set II according to the paper :

Z. Y, Zhou, et. al (2010), Discrete particle simulation of particle-fluid flow...

Hi,
Can anybody tell me how to compile the changes made if we create a new solver similar to CfdemSolverPiso.
Please tell what all steps would be required as in making new folder, .C file, compiling, any changes made to bashrc etc.

Thanks a lot.

Hello Everybody,

i'm pretty new to CFD. But i have created a DEM-CFD coupled model, which run pretty good until i changed the boundary conditions. The geometry is quite simple and looks like a big hopper with a block of particles on top. After a initialisation time a wall is deleted and all particles can fall to the ground. The hopper has an inlet/outlet on the top and a second on the bottom. The side walls are defined as walls. The mesh is created with blockMesh.

Hi, I see in the liggghts script of CFDEM tutorials there are two commands "fix couple/cfd" and "fix couple/cfd/force". Besides, there is also something like
#force : f_couple_cfd[0] f_couple_cfd[1] f_couple_cfd[2]
#node : f_couple_cfd[6]
#cell id : f_couple_cfd[7]
Are they just comments or they could also be a command?
These commands are not in the Liggghts manual, I cannot find a description about them, neither in the CFDEM documents? Is there a new manual released or something?
Where can I find a description about these commands?

Hi
Any body told me if he/she used CFD-DEM for Tracing Particle clogging in microreactor (Size 1mm).
i want to know how efficient it works to Understand the concept of Clogging.
i am new so i need your suggestions.

Hello CFDEM Users,

I saw a "#define comp" switch in CFDEM new versions. I was wondering what was that for. I could guess seeing the Make/options that it is for compressible turbulence modeling. Any way tried to compile it and successfully done for CFDEM src. But It was not successful for the the compilation of Solvers. It complains that the singlePhaseTransportModel is not compatible. Have any body faced the same problems and what was the solution???

MLD

I have tried to create a simple pipe case with a pipe and adding wear to the walls.

The case runs fine up to 0.03s and then stalls for a long time and then crashes.

I cannot find out what the problem is.
Tried adjusting almost everything I think is relevant, but no luck.

Starting guess comes from a steady-state flow solution.

If one of the experts would kindly take a look at the case provided here I would be most grateful.