CFDEM®coupling - User Forum

Hi all,

Could anyone kindly tell me what the keyword 'verbous' (appeared in the couplingProperties file of ErgunTest case, v. 2.5.5) does for coupling simulations?

BR!

Lei

Hi everyone,

Hi,
I have a question if cyclic boundary conditions work with cfdemSolverPiso?

I have a square box with in-out flow in x direction and wall boundaries in y and z, which runs fine with pisoFoam and cfdemSolverPiso
When I apply cyclic boundary conditions for the flow in y direction cfdemSolverPiso fails. I can still run it without particles as a
pisoFoam case.

Thanks a lot
hj

Hi

I was just wondering what everyone else is using for discretisation schemes for their coupled models and what kind of performance you are getting? The "standard" ones that come from the tutorial cases (and also often found in OF-related literature for pure CFD cases) are:

gradSchemes: Gauss linear
divSchemes: Gauss linear or Gauss limitedLinear 1
laplacianSchemes: Gauss linear corrected
interpolationSchemes: linear
snGradSchemes: corrected

Hello all,

I need to put particles on a curved surface. In OpenFoam I can do that easily using blockMesh, but for DEM part, how can I create the wavy region to insert particles?

I used gmsh to create the curved surface with the same coordinate i used in blockMesh and saved them as .stl file to read by DEM.

When i run the file it shows the following error:
ERROR: Fix insert/stream (id ins): command requires a planar face for insertion (fix_insert_stream.cpp:230)

How can i insert partcle in a curved/wavy surface.
Any suggestion will be appreciated.

Hi All,

I am quite interested in the simulation of water drying, which is shown in the CFDEM Features. However, it is in process. Could anyone please let me know how to add the water (moisture) in the simulation system? And When this features will be released? Any suggestion and idea would be greatly appreciated！

Thanks so much~

Kun

I read what I could through the src file of cfd_coupling_convection and the convection coupling is being applied through an addendum of the DEM heat equation with a source term. In my earlier DEM simulations, I've been applying nuclear heating to pebbles and now want to consider an interstitial coolant gas. The nuclear heating is of course also with a source term added to the pebbles.

Hi

Is there any official criteria for guessing the coupling interval size and/or CFD timestep size based on particle/fluid properties? (DEM has the Rayleigh and Hertz criteria based on particle properties for particle collision time steps)

Or is it just a matter of trial and error (experience) to find what works best?

Cheers
Evan

Hi,

I have a problem with compiling CFDEM (2.5.5) with OpenFoam 2.1.1. It's all working fine until I do "cfdemCompCFDEM". The resulting errors are (see the attachment for the complete log file):

Hello,

I modified blockMeshDict and in.liggghts_init files of ErgunTestMPI case to enhance my understanding.

In CFD directory blockMesh runs good, but in DEM directory when I run the in.liggghts_init file using liggghts excutable, it shows an error-

pair_style gran/hertz/history #Hertzian without cohesion
ERROR: Illegal pair_style command

How can i overcome this error.

Please help me out.

Thanks
Manjura