I have a 100 chain by 100 bead polymer system in a solution of 320 000 single beads (LJ sigma = 0.5, m = 0.125). The system is relaxed with DPD, then NVE, NPT (first at 0.6 then 1.0), and NVT to implement the Lennard-Jones parameters and equilibrate the box (all done at zero pressure). Then before going through a controlled cooling, the system goes through an annealing cycle (instantaneously NPT 0.6 then NPT 1.0).
Since my simulations are all at zero pressure, they don't end up completing because memory is exceeded - the volume of the box blows up to 10^9 (this happens during the annealing process). What can be causing the system to blow up so much, is it just poor equilibration, every step is run at 1.0e6 timesteps and there aren't any weird deviations, everything converges.
Any help would be appreciated. Thanks