[lammps-users] How do I model Couette Flow in a NVT system with a void space
Fri, 13 Apr 2018 13:22:24 +0800
Dear Lammps users
The simulation system contains a rigid surface and a water film of 5-7 layers molecules sitting on the surface. To avoid unnecessary water-surface interactions caused by PBCs, a void space above the water is used. I am looking a way to model the Couette flow of water in this system. I know that the linear velocity profile of the fluid can be obtained by dragging a wall or used fix nvt/slood and fix deform commands. But I don't want my box be deformed and I also don't want the water confined in a channel. I tried to add a velocity parallelingto the surface to water molecules in the upper-most layers. However, the volume of the water is changed due to the void space. Thus, it's difficult to define the water molecules in the upper most layer. How can I do to get the couette flow in this system?