CFDEM®coupling - User Forum

Hi,

I am new to this code and so far have been enjoying it.
I managed to get the two spheres tutorial case running for the immersed boundary solver.

My question is: Can I connect multiple spheres together to create a shape, give said shape material properties through the links between each individual sphere, and run the immersed boundary solver in CFDEM-public release?

Thanks
Andrew

Hi All,

I am new to simulations but a fast learner.

I installed ParScale (https://github.com/CFDEMproject/ParScale-PUBLIC) and am trying to run and visualize the example here (https://github.com/CFDEMproject/ParScale-PUBLIC/tree/master/examples/tes...).

Hi, I have problems compiling CFDEMCoupling on a Linux machine (Fedora34). I first had problems with VTK and compiling Liggghts. I used the auto makefile and switched auto install of VTK to on. However, I still had to set CFDEM_ADD_LIB_PATHS and CFDEM_ADD_LIBS in additionalLibs_5.x to get the compilation to work. I set the paths according to the following post: https://www.cfdem.com/comment/19083#comment-19083

setting：ErgunTestMPI
momCoupleModels: implicitCouple
forceModels: DiFeliceDrag, gradPForce, viscForce

In the script of LIG of ErgunTestMPI case: fix cfd2 all couple/cfd/force/implicit → it produces f_cfd2 and f_dragforce
probeModel: particleProbe → it produces DiFeliceDrag, gradPForce, viscForce.
IOmodel: trackIO → it produce DEMForces, impForces

What are the differences between f_cfd2, sum(f_dragforce), DEMForces?

Does the seed numbers used in initialization (in.liggghts_init) and run (in.liggghts_run) script require to be different? I am using initialisation script to generate the bed and run script to insert some particles with fluid on prepared gravel bed.

Can you please explain what is the difference between U, Us, and vSmoothField?

Dear CFDEM users and developers,

I have installed CFDEM coupling software and run the case ErgunTestMPI to do run test.
It reports the following error: cannot remove '/home/ann/TEST/cfdemSolverPiso/ErgunTestMPI/log_run_parallel_cfdemSolverPiso_ErgunTestMPI_CFDEM': No such file or directory
Decoposing case.
....
(please see the attached screen shot)

Could you please tell me how to solve this problem?

Thank you in advance.

Best wishes,
Ann

Hi all,

I try to do a simple CFD-DEM coupling simulation so as to validate our new drag force model. Thus I canceled the "gradPForce" and "viscForce" force models, however, the solver complains that the two forces are not defined.

My questions is that the two force models are essential and could not be cancelled? Do you have some suggestions on fixing the problem?

Regards,
Yutian

Hey
Can anyone tell that while running the cfdem tutorials, after running the DEM script I am not able to couple the CFD and DEm together. What command should I use to run the Allrun script.

Hi everyone,
I am looking at my results at different steps of Immersed boundary method in cfdemSolverIB. The question is that why the intermediate pressure for a settling particle is something like the first attached image. On the other hand, using some correction for imposing particle velocity, the pressure field is modified to the second image and this field is used for drag calculation. Can anyone tell me more about the differences between these two steps?