Dear Lammps Users,
I need to simulate nano-flow in x direction which is confined by two parallel walls normal to z direction. There are three layers of wall atoms in each wall. I divided 6 groups for every wall along with x direction and temperature for each group (T1(constant) < T2(constant) < T3 (constant) < T4(constant) < T5(constant) < T6(constant)) is varied. There are around 50,000 atoms for every wall and 20,000 fluid atoms.
In simulation, * f * style boundary is used in z direction and periodic boundary conditions are used in x and y direction. Initialising velocity for each group wall atoms while do not perform updating wall atoms’ velocity and position. LJ potential is used to calculate interactions for wall-wall, wall-fluid and fluid-fluid atoms.
My question is that some fluid atoms go through the walls in z direction and the simulation is terminated. So what can I do to solve this problem, creating more wall atoms or using WCA potential rather than LJ for wall-fluid interaction?
Also, I am not sure that, for a wall, thermostatting for every group wall atoms under different constant temperature can be done by using idealized wall instead of rough wall (made of particles) in z direction. If yes, I may use * fix wall/reflect * command so that fluid atoms may not go through wall.
Thank you.
Best wishes,
Qiangqiang Sun