Time dependent heat source

Submitted by bmercer on Tue, 12/13/2016 - 20:18

Hello LIGGGHTS users,

I'm trying to set up a heat source which changes with time. The documentation suggests that it should be possible to set up a time and/or space-dependent heat source by using the set command and using an atom-style variable. Space dependence works for me, but time does not. Below is a simple example of how I specify a time-dependent heat source:

variable H atom step
set atom * property/atom heatSource v_H

I dump both f_heatSource[0] and v_H as per-atom quantities, and it looks like f_heatSource[0] takes on the value of H at the first step in the simulation and does not change in time, while the variable v_H takes on the current step value, as I've assigned it.

How can I get the heat source to update in time as the simulation progresses? Is there a different command I should use? Is this something that would require some programming?

Thanks very much for any thoughts. I am using LIGGGHTS 3.5.0.

Forums:

Daniel Queteschiner | Wed, 12/14/2016 - 10:03

If I remember correctly, you need to invoke the set command every time you want to change the property/atom, e.g. using the run command with the 'every' option:
run X every Y "set atom * property/atom heatSource v_H"

bmercer | Thu, 12/15/2016 - 18:13

Thanks! The 'run' command with the 'every' option works perfectly.