unfix at specific time step CFDEM

Submitted by uhelfenstein on Thu, 04/03/2014 - 17:37

Hi,

I set up a coupled simulation where particles are conveyed within an air stream into a container. After a while I want to unfix the bottom of the container to empty.
Within a DEM simulation I would do it with a "run xxx upto" command and than a "unfix" command. But according my understanding in a coupled simulation (CFDEM) there is always one timestep ("run 1") executed. How can I execute a unfix command after a specific time? Is it possible with a liggghtscommand within the CFD/constant folder?

Thanks for Help,

Urs

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cgoniva's picture

cgoniva | Thu, 06/26/2014 - 12:13

Hello Urs,

that's right, liggghtsCommandModel execute can do that job.

Cheers,
Chris

uhelfenstein | Thu, 07/03/2014 - 09:11

Hi,

The case mentioned above I solved by running different simulations and put the results together by hand. But for the future I want to be prepared to solve the problem more sophisticated. Therefore, I want to ask if there is anyone who could share an example of the "constant/liggghtsCommands" file which executes a LIGGGHTS command (e.g. an unfix command as mentioined before) at a certain time step.
Are there any other settings which need to be applied to run this commands?

tks,

Urs