Using Results of one Simulation as Init for another Simulation

Submitted by gilgamesch on Thu, 08/22/2019 - 09:15

Hello guys,

I am fairly new to LIGGGHTS and DEM in general, so you will probably read my name a few more times in the future.

I created an input file and ran a few simulations where I insert particles using insert/pack in a box shaped region inside my domain to for a plateau. So far so good. In the next step I would like to use the end result of one of these simulations as the starting state for any following simulation, so that I don't need to waste precious simulation time on building the same plateau on every run. (I hope this makes sense so far.)

I did some research on my own, but couldn't find any information on how to read the output file (it's a .vtk file) into any input script. The documentation does not mention any way to do that either. I tried read_data myfile.vtk but as expected LIGGGHTS does not know what to do with it and throws an error (Unknown identifier in data file).

I don't know what files could be useful here so I didn't include any.

Thank you guys in advance


gilgamesch | Fri, 08/30/2019 - 11:23

Thank you for your reply! I tried the write and read functions as follows:

For the first run of the simulation. This was written in the document so I tried using it.

# Insert particles
run 50000 upto

write_restart restart.equil

unfix ins

Then for the rerun.

# Input Script for Simulation
read_data restart.equil
run 50000

However I can't get it to work. It says:
ERROR on proc 0: Unknown identifier in data file: �& (../read_data.cpp:642)

Hope you can help me with this as it would speed up my research quiet a bit.

Thank you in advance!