CFDEM®coupling - User Forum

Hi,
I tried to model a sphere in a fluid. It should be obey the Stoke's flow and the reynold number should be very small. Does anyone know where to set the reynold number? In addition, the transport model for my simulation is Newtonian. Is it related to the change of reynold number? Thanks.

Hello, I work with resolved CFDEM and it seems there is alimit in the number of cells that can be inside of a particle. I get the error:

big particle algo found more cells (1004) than storage is prepered (1000)

Anyone faces the same problem?

Hello:

Just a simple question. When I run CFDEM in parallel I have to put in file parCFDDEMrun.sh the required number of processors. Additionally I have to put it in decomposeParDict for OpenFOAM. Then my question is, do I have to put the number of processors in file in.liggghts_init of LIGGGHTS using the command processors?.

Best regards.

Rafael

I've followed instructions for installation of CFDEM coupling, and have got to part where the various paths can be tested using 'cfdemSysTest'.

However, this gives output below.

Some of the LIGGGHTS directories are missing. I have used the tar source, rather than git, as git is not available on our system.

Can you say why the PIZZA and mylpp directories are missing in my LIGGGHTS installation ? The directory listing of $HOME/LIGGGHTS/LIGGGHTS-PUBLIC is

Hi All,

I have already run the coupling test example of the CFDEM. And I am wondering how to watch the result as animiation in the paraview. I notice for the cfdemPostproc, after running, the paraview is open automaticly. But for other case, I have no idea how to do it.

Any suggestions and helps are highly appreciated.

Thanks!

Kun

if(verbose_ && index >=0 && index <2)
{
Info << "index = " << index << endl;
Info << "gradP = " << gradP << endl;
Info << "force = " << force << endl;
}
I wrtie "verbose" under the gradpprop item in the couplingproperties file.

How can I get the data

Is it possible to download CFDEM Coupling software without using git ? We don't use this currently on our cluster. Is there are tar available ?

We have previously built OpenFOAM and LIGGGHTS from source, not using git.

thanks,

Colin

I simulate the bubble's movement in the water and the bubbles are regard as discrete elements. At the start of calculation, the bubble velocity is not equal to 0, and the liquid velocity is equal to 0, the pressure gradient of the liquid flow field is 0, therefore the buoyancy of air bubbles is 0, but the drag force is not 0, So if the bubbles inject into the flow field in the horizontal direction ,they will be move downward under the drag effect, which is obviously not realistic. How to solve this problem?

My case computation takes a lot of time. So I want to kown, If I interrupt the calculation, how to save the results, including CFD and DEM sides, and next time I can continue to compute using the previous calculation results as initial conditions.

For model A simulations, the viscous force is applied in addition to the particular drag model (Schiller Naumann, Koch Hill, DiFelice or Gidaspow). I have read over the paper by Zhou (2010) 'Discrete particle simulation of particle-fluid flow: model formulations and their applicability' and I have seen that this viscous force term is included in their eqn 2.13, the sum of forces on a particle.