How to run Liggghts in CFDEM

Submitted by lixuethermal on Tue, 02/25/2014 - 06:19

I have installed CFDEM and run some cases successfully.

In order to save computational time, I like to run Liggghts first to get the initial position of particles and then use the results as restart file for CFDEM calculation.

Does anyone can tell me how to run Liggghts separately ? The command Liggghts does not work.

Many thanks

Peter

Forums:

alice's picture

alice | Wed, 02/26/2014 - 14:41

Hello Peter,
in some of the tutorial cases this procedure is applied (e.g. in ErgunTestMPI, just to name one). Have a look at the *.sh files, which contain all the comands necessary for running the complete case.
Cheers,
Alice

RjwV | Fri, 03/14/2014 - 14:42

Hello Peter,

In the ErgunTestMPI tutorial you could run LIGGGHTS by typing cfdemLiggghts in.liggghts_init to initialize your particles in the position you would like them to be. Afterwards you can decompose your CFD case and run it in parallel, make sure in coupling properties the correct liggghts file is selected (I believe in.liggghts_resume in the ErgunTestMPI case...). This way you will not need to use the Allrun file.

Don't forget to save your simulation data in a results folder before restarting (and possibly overwriting) your previous simulation!

Kind regards.

cgoniva's picture

cgoniva | Wed, 04/02/2014 - 09:48

Hi,

besides the command
cfdemLiggghts in.liggghts_init

you can use
cfdemLiggghtsPar in.liggghts_init 2 (for 2 procs)

Kind Regards,
Chris

marcelo | Tue, 03/21/2017 - 14:36

Hi,

I run the case with cfdemLiggghts in.liggghts_init, and before this, his log.liggghts has:

Dangerous builds = 0
#dump dmp all custom 1000 post/dump.liggghts_init id type type x y z ix iy iz vx vy vz fx fy fz omegax omegay omegaz radius
dump dmp all custom/vtk 1000 post/liggghts_init*.vtk id type type x y z ix iy iz vx vy vz fx fy fz omegax omegay omegaz radius
ERROR: Invalid dump style (../output.cpp:591)

How I can see the results in ParView?

j-kerbl's picture

j-kerbl | Thu, 03/30/2017 - 13:23

Hi Marcelo,

i guess you haven't compiled LIGGGHTS with VTK support. So comment the line "dump .... custom/vtk" and uncomment "dump .... custom" to use regular dump files. After the simulation you have to use lpp to convert dump files to vtk to be able to see them with paraview.
Lpp is a small python tool, which uses the python-numpy package, https://github.com/CFDEMproject/LPP

Cheers,
Josef