grid 8 1 8
cell_dimensions 1 1 1

flow incompressible
xy_boundary free_slip
yz_boundary free_slip
zx_boundary free_slip
viscosity 0.1
gravity 0

initial_particles everywhere random
density 64

initial_velocity zero

u 3 0 3 10
u 3 0 4 -10
w 3 0 3 -10
w 4 0 3 10

u 3 0 2 10
u 3 0 5 -10
w 2 0 3 -10
w 5 0 3 10
