LAMMPS (5 Oct 2007) # 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) 1 by 1 by 1 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 dump 1 all atom 100 dump.obstacle #dump 1 all custom 100 dump.custom tag type x y z vx vy run 25000 Memory usage per processor = 1.36032 Mbytes Step Temp E_pair E_mol TotEng Press Volume 0 1.0028598 0 0 0.68791746 0.4628783 1142.8674 1000 1 -0.37328511 0 0.31267068 1.3684627 1268.502 2000 1 -0.37505949 0 0.3108963 1.1534403 1304.1442 3000 1 -0.47919489 0 0.20676089 1.4549832 1322.0606 4000 1 -0.48849092 0 0.19746486 1.4619445 1361.4653 5000 1 -0.5158306 0 0.17012519 1.3415433 1399.8571 6000 1 -0.46839183 0 0.21756396 1.1363632 1433.3799 7000 1 -0.4934634 0 0.19249239 1.1974639 1438.8597 8000 1 -0.43365481 0 0.25230098 1.1237932 1444.8858 9000 1 -0.38250014 0 0.30345564 1.0808676 1445.4458 10000 1 -0.41296265 0 0.27299313 1.0868711 1444.8934 11000 1 -0.3906263 0 0.29532949 1.0008831 1443.6394 12000 1 -0.41935827 0 0.26659752 1.0104839 1435.183 13000 1 -0.35477192 0 0.33118387 0.94488941 1440.5498 14000 1 -0.39497861 0 0.29097718 1.072787 1435.3595 15000 1 -0.38656691 0 0.29938888 1.05116 1442.1287 16000 1 -0.37132523 0 0.31463056 1.0827132 1450.8796 17000 1 -0.37146616 0 0.31448963 1.1724883 1450.3808 18000 1 -0.38747606 0 0.29847973 1.0753661 1455.6913 19000 1 -0.37206204 0 0.31389375 1.0665364 1450.8326 20000 1 -0.39878843 0 0.28716736 1.0958347 1453.0454 21000 1 -0.36006462 0 0.32589117 0.92452983 1459.3281 22000 1 -0.36787908 0 0.3180767 0.9659935 1465.6707 23000 1 -0.36909747 0 0.31685831 0.9769748 1470.1647 24000 1 -0.38163837 0 0.30431741 0.99582238 1458.5709 25000 1 -0.38524202 0 0.30071376 0.96693615 1458.596 Loop time of 3.18151 on 1 procs for 25000 steps with 769 atoms Pair time (%) = 0.885881 (27.8447) Neigh time (%) = 0.198662 (6.24426) Comm time (%) = 0.052001 (1.63448) Outpt time (%) = 0.45079 (14.1691) Other time (%) = 1.59418 (50.1075) Nlocal: 769 ave 769 max 769 min Histogram: 1 0 0 0 0 0 0 0 0 0 Nghost: 43 ave 43 max 43 min Histogram: 1 0 0 0 0 0 0 0 0 0 Neighs: 1642 ave 1642 max 1642 min Histogram: 1 0 0 0 0 0 0 0 0 0 Total # of neighbors = 1642 Ave neighs/atom = 2.13524 Neighbor list builds = 1639 Dangerous builds = 0