CFDEM®coupling - User Forum

when I run the liggghts, I can use insert/pack or insert/stream to insert particles continously. But when I run the cfdem case, it dose not work.

I don't kown the reason. I think it's because the coupling interval.

Thanks for any opion about insert particles contiously.

Thanks,
Zhao

Hi,

It's seems to me that bigParticles model is not managing well the calculus of voidFraction field with periodic BC or parallel computing. Indeed, voidFraction is not the same at each side of the boundary or between 2 processors.

In the image, it is voidfractionfield after first step of calculation where the rectangular mesh is divided in 4 processor (as a cross) and periodic at each side. One can clearly see the processor separation (orange cross) even if the particles are randomly distributed on the rectangle...

How to fix that ?

j

Hi,

I'll tried to upgrade from CFDEM-PUBLIC-2.1.0 to CFDEM-PUBLIC-2.1.1, everything works fine during compilation.
But when solvers compile, there's an error :

/usr/bin/ld: cannot find -llagrangianCFDEM-PUBLIC-2.1.1

So I tried to come back to previous OpenFoam version 2.1.0, by changing $WM_PROJECT_VERSION variable to 2.1.0, and recompiling, but now, I get the same error when compiling solvers:

/usr/bin/ld: cannot find -llagrangianCFDEM-PUBLIC-2.1.0

I made a: locate lagrangianCFDEM-PUBLIC and it eventually find a lib file :

Dear All,

When I am running "settlingTestMPI" on the Cluster the following Error apears:

Writing polyMesh
----------------
Mesh Information
----------------
boundingBox: (0.045 0 0.045) (0.055 0.05 0.055)
nPoints: 9261
nCells: 8000
nFaces: 25200
nInternalFaces: 22800
----------------
Patches
----------------
patch 0 (start: 22800 size: 400) name: atmosphere
patch 1 (start: 23200 size: 2000) name: walls
End

Failed to parse arguments: Cannot open display:

Hello Everyone, I want to simulate a bubble column which bubbles spray out from a gas distributor into water.

Bubbles were considered as the discrete phase and their flow behaviour was simulated using DEM. The water phase was continua phase which was simulated using Euler method. The diameter of bubbles was supposed to be a constant(5mm).

I want to use Herz-Mindlin Granular contact model to complete the simulation. I just consider the bubbles the same as any other solid particles simply.

Can I use liggghts to simulate the bubbles contact?

Hi

My log files end up being really big (~10GB) and I don't find any use for the "log.liggghts" file that is output to the /case/CFD/ folder.

Is there a setting that stops this file from being created?

Thanks
Evan

Hello, I'm studying the flow above a wing, for a project of ice accretion. For this work it is necessary to study the water particle tracks. Should you advice the CFDEM method? Could you indicate me a link that explain how to use CFDEM method?
Thanks.

Best regards.
Mattia Garabelli

Hi,everyone!
I want to define a new drag model and use it in my simulation.

here's my steps:

1 I made a new directory named 'Newdrag' in ../submodels/forcemodel, and wrote my Newdrag.C and Newdrag.H there.

2 Then I modifiled 'files' in ~/CFDEM/CFDEMcoupling-PUBLIC-2.1.1/src/lagrangian/cfdemParticle/Make(just add an item '$(forceModels)/NewDrag/NewDrag.C' after item '$(forceModels)/GidaspowDrag/GidaspowDrag.C )', and ran 'wmake' at ../~/CFDEM/CFDEMcoupling-PUBLIC-2.1.1/src/lagrangian /cfdemParticle to compile the NewDrag.C.

Hi,

I read in the documentation for the bigParticle voidfraction model that:

The bigParticle voidFraction model is supposed to be used when a particle (or it's representation) is bigger than a CFD cell. The voidfraction field is set in those cell whose centres are inside the particle which results in a stairstep representation of the bodies within the mesh (i.e. voidfraction is either 1 (fluid) of zero (solid)). For archiving accurate results, approx. 8 cells per particle diameter are necessary.

Hi,

May I ask a question about the momentum transfer between solid and fluid phases?

Where can I specify the range of the forces included for momentum transport from solid phase to fluid?

Is MeiLift included? Could anyone give me a clue?

Thanks.

rq