CFDEM®coupling - User Forum

Hello all

I am facing this strange problem using 'fix freeze' command. I generated bed consisting of large particles (type 1). I want my bed to not move at all when injecting small particle (type 2) along with the fluid from inlet. To achieve this, I tried freezing the large bed particle (type 1). In my run script, I group the type 1 particles and then freeze them, the freeze command is located after cfd fixes, so that the forces coming from CFD side also becomes zero and bed should remain stable.

Hi,
I'm running a case with an filtration application. It is laminar flow, a set of fixed particles as a membrane and some moving particles within the flow.
After a certain amount of time, the kinetic energy increases very fast and the run breaks up.

What could be the reason for the increase in kinetic energy?

Hi,
I am about to make a simulation where the first part of the domain is nonsloping, but the second part of the of the domain should be sloping. It is a beach where the first part is at constant depth and then the sloped part, where the depth is decreasing until reaching the surface. Is it possible to make such a domain in LIGGGHTS?
I have attached a picture of the domain I want to create.

Hello everyone.

Hello

I know that it is the basic assumption and a prerequisite in unresolved CFDEM that the particle diameter must be smaller than CFD cell size. It is recommended that that cfd cell should be around 10*particle diameter.

Hello Community

I am facing a problem where I am not able to provide periodic boundary at STL boundaries which are inside the larger simulation box. In the CFD side, I am providing the cyclic bc at inlet and outlet of stl geometry. However, In DEM side, I cannot find any option where I can provide periodic bc at inlet and outlet STL boundaries. As per my understanding, in the liggghts scripts, we define boundary type of simulation box, not of STL boundaries. I looked in the portal but could not find the answer. I wonder, if I can do it anyway?

Hi, experts,
Recently I try to couple cfdem inserting superquadric models. But the error always shows in my case like "ERROR on proc 0: Using default surface model for non-spherical particles! (../surface_model_default.h:144)" .
After I seeking for the code, it told that
"if(sidata.is_non_spherical)
error->one(FLERR,"Using default surface model for non-spherical particles!");"
I am a little confused about the meaning of the "sidata". Could anyone give some explanation and advice .

Thx so much,
Clyde

Hi Guys

Does anyone have any advice for modelling deck of vibrating screens?

I have developed a mesh 2x1.8m with 12.5mm apertures in it.

I get the below error when trying to run my code.
what can I do to resolve the issue?

Hi

Dear everyone
I am working a soil scour problems, recently, I found a modified version of CFDEM with multiscale CFD/VOF-DEM solver developed by Linhan Ge called CFDEMCoupling-LG. However, when I installed it according to the Installation procedures provided in "readme" file, all the tutorials can not run well including the tutorials of the original CFDEM version. Has anyone ever encountered such a problem？
Zhang Peiyun
Tongji University