[lammps-users] About strain rate

If I want to apply a tension load at a certain strain rate, can I use fix setforce or velocity command except fix deform command. I dont know the original difference among them.
any advice would be appreciated. thanks.


The major difference is that the fix setforce and velocity commands do
not change the size of the simulation box. Fix deform does change the
simulation box size. You probably want to use fix deform. I'd
recommend carefully reading through the fix deform documentation page:



Hi Han,
I have tried both options ( in some of my test simulations) but I do not see any significant change in the stresses (in the initial part of the curve at least). However, If you want to use velocity command specifically, you would have to increase the size of the box beforehand ( you can do that by using displace_box command). They may hinder you computational power if you want to run your simulations in parallel as there would be a lot of empty space ( in the system you are simulating).