[lammps-users] Equilibration of confined polymer melt!

Dear users,

I am trying to equilibrate the polymer melt confined between two walls.
After a few runs the polymers blow out of the simulation box.
Small time steps, gradual increase of amplitude of the soft potential doesn’t help.
Here is the input file and data file. This same script with
“boundary p s p” works very nice. But since we are interested in confined
the fluid from all sides we use “p s s” and as soon as we apply this the melt
blows out of the simulation cell. Any input will be appreciated.


wall.data (276 KB)

equil.in (1.56 KB)

If converting a periodic boundary condition to non-periodic causes
stuff to fly apart, then it was likely being held in place
by the periodic boundary. So if you have overlaps and the
system is at pressure, then removing the constraint could
cause that to happen. Try to figure out why your polymers
are being blown out of the domain.