LAMMPS (10 Jan 2012) # 2d LJ obstacle flow 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 40 0 10 -0.25 0.25 create_box 3 box Created orthogonal box = (0 0 -0.321089) to (51.3743 22.2457 0.321089) 4 by 1 by 1 MPI processor grid create_atoms 1 box Created 840 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 1 120 atoms in group lower region 2 block INF INF 8.75 INF INF INF group upper region 2 120 atoms in group upper group boundary union lower upper 240 atoms in group boundary group flow subtract all boundary 600 atoms in group flow set group lower type 2 120 settings made for type set group upper type 3 120 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 # Poiselle 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 -0.5 0.0 fix 6 flow addforce 1.0 0.0 0.0 # 2 obstacles region void1 sphere 10 4 0 3 delete_atoms region void1 Deleted 36 atoms, new total = 804 region void2 sphere 20 7 0 3 delete_atoms region void2 Deleted 35 atoms, new total = 769 fix 7 flow indent 100 sphere 10 4 0 4 fix 8 flow indent 100 sphere 20 7 0 4 fix 9 all enforce2d # Run timestep 0.003 thermo 1000 thermo_modify temp mobile WARNING: Temperature for thermo pressure is not for group all (thermo.cpp:442) dump 1 all atom 100 dump.obstacle #dump 1 all custom 100 dump.custom id type x y z vx vy run 25000 Memory usage per processor = 2.0558 Mbytes Step Temp E_pair E_mol TotEng Press Volume 0 1.0004177 0 0 0.68689281 0.46218884 1142.8674 1000 1 -0.32494012 0 0.36166587 1.2242587 1282.3056 2000 1 -0.37815616 0 0.30844982 1.0644647 1312.3508 3000 1 -0.49062349 0 0.1959825 1.524186 1322.0444 4000 1 -0.50104961 0 0.18555637 1.4608096 1367.4322 5000 1 -0.46523216 0 0.22137383 1.3335657 1406.7051 6000 1 -0.47059773 0 0.21600825 1.2548634 1423.0902 7000 1 -0.44657953 0 0.24002645 1.106616 1436.7658 8000 1 -0.43539162 0 0.25121437 1.0742654 1442.8753 9000 1 -0.38186467 0 0.30474131 1.0117035 1447.3876 10000 1 -0.39896866 0 0.28763732 1.0524893 1446.5995 11000 1 -0.37849424 0 0.30811174 1.0893542 1442.4734 12000 1 -0.39472467 0 0.29188132 1.0838529 1443.7807 13000 1 -0.37490702 0 0.31169896 1.1173928 1457.8891 14000 1 -0.36757971 0 0.31902627 1.027341 1463.8882 15000 1 -0.40485222 0 0.28175376 1.0862575 1461.3309 16000 1 -0.38136304 0 0.30524295 1.0094705 1460.0656 17000 1 -0.37412919 0 0.3124768 0.99444621 1458.5668 18000 1 -0.36780296 0 0.31880302 0.99102309 1454.7293 19000 1 -0.36676642 0 0.31983956 0.98342341 1456.8015 20000 1 -0.39037633 0 0.29622965 1.0065285 1458.0052 21000 1 -0.37528404 0 0.31132195 0.93202146 1457.1218 22000 1 -0.40600625 0 0.28059973 1.0458453 1457.5121 23000 1 -0.37632791 0 0.31027808 0.91482419 1461.225 24000 1 -0.37066269 0 0.31594329 0.97118976 1456.6596 25000 1 -0.39711429 0 0.28949169 0.99340063 1456.4638 Loop time of 0.985739 on 4 procs for 25000 steps with 769 atoms Pair time (%) = 0.12752 (12.9365) Neigh time (%) = 0.0371044 (3.76412) Comm time (%) = 0.235177 (23.858) Outpt time (%) = 0.113567 (11.521) Other time (%) = 0.47237 (47.9204) Nlocal: 192.25 ave 234 max 156 min Histogram: 1 1 0 0 0 0 0 1 0 1 Nghost: 42 ave 50 max 38 min Histogram: 2 0 1 0 0 0 0 0 0 1 Neighs: 405 ave 561 max 281 min Histogram: 2 0 0 0 0 0 0 1 0 1 Total # of neighbors = 1620 Ave neighs/atom = 2.10663 Neighbor list builds = 1629 Dangerous builds = 1