CFD and DEM - General Discussion

Hi,
I have made a box filled with particles and I want to apply a certain pressure on them. To apply the pressure a mesh wall moves down to compress the particles. However, I want to let the wall move till a certain pressure value is met. I tried to do so by making the mesh move inside the loop untin the pressure limit is met.
The problem is that I do not know how the calculate the pressure and implement it in the loop.
I have tried compute wall/gran/local force to calculate the force on the mesh, but i am not able to use the output parameters in my loop.

Hi guys,

I am going to simulate a number of lagrangian bubbles in eulerian continuum fluid phase using CFDEM-LIGGGHTS-OPENFOAM. I have installed CFDEMProject with LIGGGHTS and OpenFOAM-Paraview.

Can anyone help me by telling is that possible or not and if it is possible, which solvers in CFDEM i should use. And how should i proceed step-by step to do the simulation.
If openfoam can do this, please tell which solver and files in openfoam can do that.

Hello Everybody,

I am currently dealing with a simulation of particles in closed geometries (Cylindrical Pipes). Till now, I used the DEM solver in Star-CCM to simulate the flow of particles in vertical pipes. The flow is in dense phase (packing fraction ~ 60%) and is solely driven by gravity. Hence I decoupled the air and the particles and got good/accurate results.

I need to insert particles into the container I made in stl format (as servo wall). Can anyone send me the command for running it in liggghts. I tried the commands on tutorial but it doesnt work. A lot of error and warning messages are showing. Some may be due to the version change. Could anyone pls send me a working command in txt format

Hi, How can i create surface files in stl format so that it can be opened in paraview

Hamburg University of Technology (Germany) offers a research
position for the two-year project "Multiscale modelling of physical
processes along water-soil interface" based on CFD-DEM coupling
using OpenFOAM and LIGGGHTS. For details see homepage

http://intranet.tuhh.de/aktuell/stellen/stelle.html?kenn_nr=D-15-160

or ask Dr. Hans Hügel (h.huegel@tuhh.de).

Hi Guys,

I am desperately looking for a complete step by step guide on how I can install liggghts on my mac book air. Can anyone help me please.

thanks

Hello Everybody,

My study is dedicated to create packed bed of spheres and run simulation CFD to investigate the mass and heat transfer in the packed bed reactor. The problem I found when I create a packed bed of spheres with the script "in.packing" is that some spheres do not each other well and in some spheres there is a overlapping. This problem will affect the generation of the mesh. My question is if I can avoid this problem creating a packed bed without overlapping so just with normal contact points between the spheres and the wall ?

Hi,

I read the thread in the FAQ for hardware selection from user Richti and I'm wondering if it is still up-to-date, that 'DELL T7600 2x8' is one of the best machines for LIGGGHTS simulation. It would be nice if there exists something like an ASIC just for the DEM calculations. If some of you have some information about best hardware for LIGGGHTS I would really be interested in.

kind regards
Joshua

Dear everyone,

I'm working on a coupling case and I want to investigate the influence of fluid properties.

When I use water to couple with particles, the result is fine. However, after I change the water into a HerschelBulkley fluid, the code cannot run any more.

After the timestep is adjusted, the code can run. But still, the result is quite strange.

Is there any coupling problem due to the change of fluid property?
Is the divergence related with the viscosity of the fluid?

Many thanks for your attention.

Regards,
Moon