LAMMPS (22 Jan 2008) # 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 Lattice spacing in x,y,z = 1.28436 2.22457 1.28436 region box block 0 20 0 10 -0.25 0.25 create_box 3 box Created orthogonal box = (0 0 -0.321089) to (25.6871 22.2457 0.321089) 2 by 2 by 1 processor grid create_atoms 1 box Created 420 atoms 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 60 atoms in group lower region 2 block INF INF 8.75 INF INF INF group upper region 2 60 atoms in group upper group boundary union lower upper 120 atoms in group boundary group flow subtract all boundary 300 atoms in group flow set group lower type 2 60 settings made for type set group upper type 3 60 settings made for type # 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 50 dump.flow run 10000 Memory usage per processor = 1.67714 Mbytes Step Temp E_pair E_mol TotEng Press Volume 0 1 0 0 0.71071429 0.5223703 571.43371 500 1.0967867 -0.3465085 0 0.43299345 3.2514265 571.43371 1000 1 -0.36129869 0 0.3494156 3.1353617 571.43371 1500 1.1299217 -0.37859354 0 0.42445794 2.9270341 571.43371 2000 1 -0.34287506 0 0.36783923 3.0258649 571.43371 2500 1.0916596 -0.3872134 0 0.38864469 2.8426168 571.43371 3000 1 -0.42816199 0 0.2825523 2.7129793 571.43371 3500 0.94744822 -0.47483071 0 0.19853427 2.7259788 571.43371 4000 1 -0.3684736 0 0.34224069 2.6328623 571.43371 4500 0.99502131 -0.37808208 0 0.32909378 2.5909215 571.43371 5000 1 -0.41230276 0 0.29841152 2.9229369 571.43371 5500 1.0560855 -0.48401682 0 0.26655822 2.472482 571.43371 6000 1 -0.4068915 0 0.30382279 2.3428133 571.43371 6500 1.0437572 -0.41914338 0 0.32266981 2.6151758 571.43371 7000 1 -0.42595992 0 0.28475437 2.3109881 571.43371 7500 1.0600587 -0.336143 0 0.41725588 2.3511832 571.43371 8000 1 -0.40369591 0 0.30701838 2.6195769 571.43371 8500 1.0750756 -0.43763885 0 0.32643275 2.2469938 571.43371 9000 1 -0.44198063 0 0.26873366 2.5250617 571.43371 9500 1.0263815 -0.43395816 0 0.29550586 2.5922753 571.43371 10000 1 -0.47197889 0 0.23873539 2.4144186 571.43371 Loop time of 4.11115 on 4 procs for 10000 steps with 420 atoms Pair time (%) = 0.0713452 (1.73541) Neigh time (%) = 0.0230771 (0.561329) Comm time (%) = 3.20043 (77.8475) Outpt time (%) = 0.163546 (3.9781) Other time (%) = 0.652753 (15.8776) Nlocal: 105 ave 116 max 95 min Histogram: 2 0 0 0 0 0 0 0 1 1 Nghost: 41.75 ave 46 max 39 min Histogram: 1 0 2 0 0 0 0 0 0 1 Neighs: 237.5 ave 301 max 178 min Histogram: 2 0 0 0 0 0 0 0 0 2 Total # of neighbors = 950 Ave neighs/atom = 2.2619 Neighbor list builds = 973 Dangerous builds = 0