CFDEM®coupling - User Forum

I am newer of CFDEM, there is a mistake when I run Tutorials. I always get this line:
rm: cannot remove '/home/administrator/CFDEM/administrator-PUBLIC-5.0/run/fillCylinder/CFD/0.*': No such file or directory

and that is the whole running process:
mesh was built before - using old mesh

// run_liggghts_fillCylinder_DEM //

/home/administrator/CFDEM/administrator-PUBLIC-5.0/run/fillCylinder/DEM

I am confused about the momentum coupling options in CFDEM viz implicit/explicit. Following are my questions.

1. what is TotalForceImp displayed in the cfdem log
is this done implicitly? sum(mesh.V()*Ksl.internalField()*(Us.internalField()-U.internalField()));

I ask this because of the next question.

2. On CFD side I have momCoupleModels selected as implicitCouple

While on DEM side for the resume file, I have: fix cfd2 all couple/cfd/force
How is the force calculated in this case? is it done explicitly?

i am newer of cfdem, there is a mistake when i run Tutorials,
it said no 0.* file, but there is a file after i see that folder, functions.sh is same
i don‘t know why

Hello Everyone,

I am a new user using the CFDEM. I am trying to use the heat transfer functions and have started with one of the tutorials (packedBedTemp). I can see that there are two main folders, DEM and CFD. In the DEM, there are also two input files: 1. in.liggghts_init and 2. in.liggghts_run. Besides, there are a few folders in the CFD folder, which I believe are the fluid properties. So, I have the following questions:

1. What is the difference between the files in the DEM folder? (the above 1 and 2 numbers).

Hello everybody,

Hallo,
I am simulating cfdem particle flow in a highly diluted fluid particle system. Particle sizes are in the range of 100µm, expected particle velocities on the scale of 100m/s. I have a question on the neighbor definition.
Currently I am using the following neighbor definition:
neighbor 1e-3 bin
When I decrease the value to 1e-4 it significantly slows down my simulation.
How can I estimate the proper choice for the neighbor definition?
Best
kalei

Hi all, I am trying to set up a simulation where particles are inserted in an extreme of a rectangular pipe. I have inserted them either with constant and gaussian velocity but when I visualize the results some of them start their motion with an extremely high velocity.

From the other hand I have been struggling trying to put a movile surface that compress the particles (along the z axis). So far, I have found that I should use servo command, but when I add to the DEM file the folowing instruction:

Dear all.
I would like to know if there is any way to create a restart file after a simulation has been stopped by using the post files of the DEM.
Thank you.

Dear All,

I have a couple of questions about the "processors command px py pz" (http://lammps.sandia.gov/doc/processors.html).
I am running a CFDEM simulation of a fluidized bed with HPC and I am trying to understand which could be the best set up for the processors.

Dear all,

When I use the CFD package in the coupling simulation, in the initial conditions of velocity, i.e. CFD-0-U, I found all the three velocity of fluid must be set in three direction (x,y,z). However, when I have a circular boundary condition, the initial velocity of fluid should be always in the radial direction. This cannot be realized just using that in x, y and z directions. My question is: is there any possibility that we exert the radial velocity boundary conditions for a circular fluid boundary? Many thanks.

Regards,
Rachel