In the example, Couette and Poiseuille flow, the boundaries are the same type and size of atom. Are there any ways that modify the boundary atoms without using the �read_data� command? Furthermore, can we put the boundary that is composed of solid, instead atoms?
You can put the boundary atoms in a group, then use the
set command to change their type. Their type is used in
the LJ potentials to set their size (sigma).
If you want a solid wall, how would it exert drag on the atoms?
You'd have to code some formula for that in a new fix you