in.flow.poiss
f4cc5550f7e2lammps-icms

in.flow.poiss
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			# 2-d LJ flow simulation

			dimension 2
			boundary p s p

			atom_style atomic
			neighbor 0.3 bin
			neigh_modify delay 5

			# create geometry

			lattice hex 0.7
			region box block 0 20 0 10 -0.25 0.25
			create_box 3 box
			create_atoms 1 box

			mass 1 1.0
			mass 2 1.0
			mass 3 1.0

			# LJ potentials

			pair_style lj/cut 1.12246
			pair_coeff * * 1.0 1.0 1.12246

			# define groups

			region 1 block INF INF INF 1.25 INF INF
			group lower region 1
			region 2 block INF INF 8.75 INF INF INF
			group upper region 2
			group boundary union lower upper
			group flow subtract all boundary

			set group lower type 2
			set group upper type 3

			# initial velocities

			compute mobile flow temp
			velocity flow create 1.0 482748 temp mobile
			fix 1 all nve
			fix 2 flow temp/rescale 200 1.0 1.0 0.02 1.0
			fix_modify 2 temp mobile

			# Couette flow

			#velocity lower set 0.0 0.0 0.0
			#velocity upper set 3.0 0.0 0.0
			#fix 3 boundary setforce 0.0 0.0 0.0
			#fix 4 all enforce2d

			# Poisseuille flow

			velocity boundary set 0.0 0.0 0.0
			fix 3 lower setforce 0.0 0.0 0.0
			fix 4 upper setforce 0.0 NULL 0.0
			fix 5 upper aveforce 0.0 -1.0 0.0
			fix 6 flow addforce 0.5 0.0 0.0
			fix 7 all enforce2d

			# Run

			timestep 0.003
			thermo 500
			thermo_modify temp mobile

			dump 1 all atom 25 dump.flow
			run 10000