Hi
I downloaded and built LIGGGHTS and CFDEM (basically following the steps in the CFDEM Coupling.pdf) with OpenFOAM-2.1.1 that was already installed on my system. As far as I can tell everything built correctly, but when running the twoSpheresGlowinskiMPI tutorial I find a strange error where the two particles don't appear to interact with the fluid in any way. I was wondering if anyone else had experienced an error like this?
After digging through the source code and adding in some extra cout statements to see what was going on, it seems that the lights_get_maxtag(lmp) function is always returning 0, and so (I think), for this reason, subsequent steps like the locateM().findCell(), and voidFractionM().setvoidFraction() don't do anything. The output from the cfdemSolverIB is just fields of zero velocity, zero pressure, etc, everywhere, while the LIGGGHTS output gives me trajectories of two particles that are accelerating downwards as expected (but their trajectories don't appear to be affected by the fluid). I've attached a snippet of the output when I try to run this tutorial, but am at a bit of a loss as to why this problem might occur. Any help would be greatly appreciated
Steve
SAMPLE OUPPUT:
Time = 0.0002
Selected 0 cells for refinement out of 500000.
Selected 0 split points out of a possible 0.
Courant Number mean: 1.96419e-14 max: 2.85282e-11
- evolve()
Starting up LIGGGHTS
Executing command: 'run 2 '
Setting up run ...
Memory usage per processor = 57.7031 Mbytes
Step Atoms KinEng 1 Volume
1 2 3.5202808e-09 0 4
3 2 3.1682527e-08 0 4
Loop time of 0.000662953 on 2 procs for 2 steps with 2 atoms
Pair time (%) = 3.95684e-06 (0.596851)
Neigh time (%) = 0 (0)
Comm time (%) = 1.47419e-05 (2.22367)
Outpt time (%) = 0.000315232 (47.5497)
Other time (%) = 0.000329022 (49.6298)
Nlocal: 1 ave 2 max 0 min
Histogram: 1 0 0 0 0 0 0 0 0 1
Nghost: 0 ave 0 max 0 min
Histogram: 2 0 0 0 0 0 0 0 0 0
Neighs: 0.5 ave 1 max 0 min
Histogram: 1 0 0 0 0 0 0 0 0 1
Total # of neighbors = 1
Ave neighs/atom = 0.5
Neighbor list builds = 0
Dangerous builds = 0
LIGGGHTS finished
timeStepFraction() = 1
- getDEMdata()
=== cfdemCloudIB::getDEMdata() === particle rotation not considered in CFD
nr particles = 0
- findCell()
findCell done.
- setvoidFraction()
setvoidFraction done.
- setForce(forces_)
setForce done.
-giveDEMdata()
giveDEMdata done.
evolve done.
DILUPBiCG: Solving for Ux, Initial residual = 0.273749, Final residual = 9.2762e-11, No Iterations 1
DILUPBiCG: Solving for Uy, Initial residual = 0.271943, Final residual = 9.3866e-11, No Iterations 1
DILUPBiCG: Solving for Uz, Initial residual = 0.703402, Final residual = 1.96173e-09, No Iterations 1
suppressing ddt(voidfraction)
legendglh | Tue, 03/15/2016 - 01:02
The same error
Hi Steve,
Have you solved this problem yet? Especially the "=== cfdemCloudIB::getDEMdata() === particle rotation not considered in CFD“ error.
Cheers,
Linhan
alice | Wed, 03/16/2016 - 14:22
Hello,
Hello,
please use an OpenFOAM-*.x version for CFDEMcoupling (best choice at the moment OpenFOAM 2.4.x) instead of precompiled binaries.
The message with the particle rotation is just an information and no error message. The used model just does not account for rotation.
Best regards,
Alice