lammps/examples/ASPHERE/ellipsoid/in.ellipsoid

117 lines
2.5 KiB
Plaintext

# SRD diffusion demo - ellipsoids
units lj
atom_style ellipsoid
atom_modify first big
dimension 2
# create big ellipsoidal particles
lattice sq 0.14
region box block 0 10 0 10 -0.5 0.5
create_box 2 box
create_atoms 1 region box
set type 1 mass 1.0
set type 1 shape 3.0 1.0 1.0
group big type 1
set group big quat/random 29898
velocity big create 1.44 87287 loop geom
# equilibrate big particles
pair_style gayberne 1.0 3.0 1.0 4.0
pair_coeff 1 1 1.0 1.0 1 1 1 1 1 1
pair_coeff 1 2 1.0 1.0 1 1 1 1 1 1 0.0
pair_coeff 2 2 1.0 1.0 1 1 1 1 1 1 0.0
neighbor 0.3 bin
neigh_modify delay 0 every 1 check yes
fix 1 big nve/asphere
fix 2 all enforce2d
compute rot big temp/asphere
#dump 1 all custom 10 dump.ellipsoid.equil id type x y z &
# quatw quati quatj quatk
thermo_style custom step temp c_rot epair etotal press
thermo 100
run 1000
#undump 1
unfix 1
unfix 2
# add small particles as hi density lattice
region plane block INF INF INF INF -0.001 0.001 units box
lattice sq 120.0
create_atoms 2 region plane
set type 2 mass 0.01
group small type 2
velocity small create 1.0 593849 loop geom
# delete overlaps
# must set 1-2 cutoff to non-zero value
pair_style lj/cut 2.5
pair_coeff 1 1 1.0 1.0
pair_coeff 2 2 0.0 1.0 0.0
pair_coeff 1 2 0.0 1.0 2.0
neigh_modify one 10000
delete_atoms overlap 1.6 small big
# SRD run
reset_timestep 0
neighbor 0.3 bin
neigh_modify delay 0 every 1 check yes
comm_modify mode multi group big vel yes
neigh_modify include big
# no pairwise interactions with small particles
pair_style gayberne 1.0 3.0 1.0 4.0
pair_coeff 1 1 1.0 1.0 1 1 1 1 1 1
pair_coeff 1 2 1.0 1.0 1 1 1 1 1 1 0.0
pair_coeff 2 2 1.0 1.0 1 1 1 1 1 1 0.0
# use fix SRD to push small particles out from inside big ones
# if comment out, big particles won't see SRD particles
timestep 0.0005
fix 1 big nve/asphere
fix 2 small srd 20 big 1.0 0.25 49894 shift yes 54979 &
collision noslip search 0.2 inside ignore exact no bounce 50
fix 3 all enforce2d
# diagnostics
compute tbig big temp/asphere
variable pebig equal pe*atoms/count(big)
variable ebig equal etotal*atoms/count(big)
thermo_style custom step temp c_rot f_2[9] etotal v_pebig v_ebig press &
f_2[1] f_2[2] f_2[3] f_2[4] f_2[5] &
f_2[6] f_2[7] f_2[8] f_2[9] f_2[10] f_2[11] f_2[12]
thermo_modify temp tbig
thermo 1000
#dump 1 all custom 1000 dump.ellipsoid id type x y z &
# quatw quati quatj quatk
#dump 1 all image 1000 image.*.jpg type type zoom 1.6
#dump_modify 1 pad 6 adiam 1 1 adiam 2 0.2
run 100000