CFDEM®coupling - User Forum

Hello all,

I'm interested to simulate a 3d system composed of a sheet of granular particles and a gas jet upon it in variable angles relative to the horizontal sheet. The velocity of the jet should be supersonic. Now, I've seen the test case video of coupled CFDEM of the partly fluidized bed, which is similar to what I want to do, though I don't know if it suits modelling of high velocity jets with different orientations of the jet source.

Is it possible to use LIGGGHTS to simulate this system ? How complicated should that be with the current version of LIGGGHTS ?

hello cfdem users,
I am trying to simulate gas-solid fluidized bed. Im learning cfd-dem coupling with the help of HopperEmpting testcase and changing the input scripts according to my case. I have packed the solid particles in the bed with the help of Liggghts and a liggghts.restart file was generated. Here's the coupling script that i used for DEM part of cfdem coupling.....

echo both

atom_style granular
atom_modify map array sort 0 0
boundary f f f
newton off

communicate single vel yes

units si
processors 1 1 2

Hi Chris,

I have two questions.
first is regarding particle-wall interactions. what happens when particles get close to walls d< rp ? in my simulations particles are passing through the walls although I have defined the walls on my geometry .

and my second question is how can I define free surfaces on the simulation? any help is appreciated as this is my first time doing a three phase with free surfaces...

Thanks,
Vajiheh

Hi,
I'm new to liggghts and CFDEM. I've just installed liggghts and CFDEM according to setup_LIGGGHTS__OpenFoamR_CFDEM_2p0_on_Ubuntu1004_24052011.txt, and that's OK.

So, I try to run the example case, settlingTestMPI. However, it failed and it showed "FOAM Fatal Error":

[1] --> FOAM FATAL ERROR:
[1] index -1 out of range 0 ... 3999
[1]
[1] From function UList::checkIndex(const label)
[1] in file /home/cfd/OpenFOAM/OpenFOAM-1.7.1/src/OpenFOAM/lnInclude/UListI.H at line 109.
[1]
FOAM parallel run aborting
[1]

Dear all,

is the void-fraction (centre) model valid for both - tet- and hex CFD-Meshes? We were performing some tests and get reasonable results for tet CFD-meshes while for a hexahedron CFD-mesh the void-fraction and therefore the fluid flow is not computed as expected.

thank you!

Hi:
I am compiling CFDEM_2 based on OpenFOAM2.0.x and LIGGGHTS1.3.3.
When compiling cfdemParticle there is an error reported
--
/OpenFOAM-2.0.x/platforms/linux64GccDPOpt/lib/libopenfoam_zp.a(postCalc.o): In function `Foam::tryCalc(Foam::argList const&, Foam::Time const&, Foam::fvMesh const&)':
(.text+0x81): undefined reference to `Foam::calc(Foam::argList const&, Foam::Time const&, Foam::fvMesh const&)'
collect2: ld returned 1 exit status
--
I searched OpenFOAM source code and did not find definition of function calc. Could anyone give some suggestions?

Hi,

I'm intending simulate a multiphase flow in a bioreactor. The initial proposal is apply a one way or two way coupling model to perform the particles behavior and residence time. Is it possible apply CFDEM - LIGGGHTS to acess this kind of flow? Does anyone have any suggestions?

Thank's in advance.

Be aware that LIGGGHTS 1.5.1 from the dev repo is currently not able to couple to CFDEM (there is a re-write underway)
Please use the latest mature version LIGGGHTS 1.5 from the git://cfdem.git.sourceforge.net/gitroot/cfdem/liggghts repo instead!

Christoph

Good morning,
I am trying to simulate the flow that is produced by Formula 1, and its interaction with particles that lays on the asphalt. Could anyone help me? Do you know if I could calculate it with this programm?

hi all,
im trying to simulate gas-solid fluidized bed with two types of different density particles. after giving 'mpirun -np 2 cfdemSolverPiso_shared -parallel' command im getting an error given below:

Executing input script '../DEM/in.insert_pack.'
ERROR: Could not open LIGGGHTS input script
--------------------------------------------------------------------------
MPI_ABORT was invoked on rank 0 in communicator MPI_COMM_WORLD
with error code 1.

NOTE: invoking MPI_ABORT causes Open MPI to kill all MPI processes.