Reaction Force- Indent

From: Rebekah Nagy
Sent: Wednesday, July 11, 2018 4:00 PM
To: Axel Kohlmeyer
Subject: Re: [lammps-users] Reaction Force- Indent

Hello Axel,

Sorry for not responding straight to the mailing list.

Thank you so much for a timely response. I am using a created sphere and not the fix indent command (sorry for the misunderstanding). Can I still use this method (assuming you are referencing using fmax in thermo style)?

​you are assuming wrong.

if you build your indenter from explicit atoms, your options are somewhat limited, depending on the details of your simulation.
this is where you have to apply your knowledge of classical mechanics. you might be able to get the information you desire through summing up the forces on the indenter atoms. this can be done either through "compute reduce sum"​ and then (again) using the thermo custom options to output the data from that compute. or you may do that through postprocessing your already exiting trajectory with per-atom force output.

depending on your setup, compute reduce may not give the desired information, then you may try compute group/group, which may or may not work for your case.

ultimately, as i mentioned before, this is a problem that boils down to simple classical mechanics of rigid bodies. so you might want to pick up a text book on that and refresh your memory on it.

​axel.​