When I am trying to run my simulation of pouring ‘V’ shape particle in the simulation box, I am facing a problem like this: “Rigid body extent > ghost cutoff - use comm_modify cutoff”. Changing the cutoff distance seems not solving the issue. I am looking for any suggestions regarding the issue. Thank you.
Most likely you are not using the recommended command correctly. But without more details or a simple way to reproduce the issue there is no way to make a meaningful suggestion.
Your input is extremely hard to read for two reasons:
you did not use triple backquotes (```) to stop the website from typesetting it and thus part of the symbols in your input are interpreted as markup instead of displayed
your input is riddled with commented out lines of code
If you want somebody to take a closer look, you have to reduce your input to the absolute minimum that is required to reproduce the issue (and especially remove all those distracting comments) and provide a complete runnable input deck. Best is also to include a log file from a test run of your own.
Ok, the problem is rather straightforward.
When you define fix rigid, you apply it to group “all”, but that will apply for rigid/small not just to the inserted objects, but also to the large group of atoms that you have already created. Such a large rigid object, however, is not suitable for for fix rigid/small. Hence the error (note the “small” in fix rigid/small).
I also is not necessary to turn those into a rigid object anyway.
if you change your input to apply fix rigid/small to only apply to an initially empty group, the rest of the input will work as it seems to be intended. and you can drop the “comm_modify cutoff 50” option at the top, too.: