LAMMPS (12 Feb 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 box = (0 0 -0.321089) to (51.3743 22.2457 0.321089) 4 by 1 by 1 processor grid create_atoms 1 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 lower atom 2 120 settings made set upper atom 3 120 settings made # 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 35 atoms, new total = 805 region void2 sphere 20 7 0 3 delete_atoms region void2 Deleted 35 atoms, new total = 770 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 = 1.44234 Mbytes Step Temp E_pair E_mol TotEng Press Volume 0 1.0006918 0 0 0.68683847 0.48039951 733.92473 1000 1 -0.3603446 0 0.32601904 1.5725867 779.90508 2000 1 -0.42832732 0 0.25803632 1.3587382 813.11821 3000 1 -0.47232806 0 0.21403558 1.4341388 844.88084 4000 1 -0.52763648 0 0.15872716 1.5459739 875.13499 5000 1 -0.48314311 0 0.20322052 1.4357888 907.02154 6000 1 -0.472141 0 0.21422264 1.3030726 924.98416 7000 1 -0.44830722 0 0.23805641 1.2882909 928.95817 8000 1 -0.43371728 0 0.25264635 1.132775 927.35692 9000 1 -0.41463177 0 0.27173186 1.1209309 921.76003 10000 1 -0.38315652 0 0.30320712 1.0966664 922.24088 11000 1 -0.37156486 0 0.31479878 1.1423804 919.78903 12000 1 -0.3742195 0 0.31214414 1.0593775 928.05099 13000 1 -0.38124076 0 0.30512288 1.1256769 929.73097 14000 1 -0.38555026 0 0.30081337 1.0946739 933.53885 15000 1 -0.40703488 0 0.27932876 1.0764066 930.2934 16000 1 -0.3725232 0 0.31384044 1.0011147 931.1519 17000 1 -0.38470452 0 0.30165912 0.99838577 928.91833 18000 1 -0.40199729 0 0.28436634 1.0888096 932.68523 19000 1 -0.37259199 0 0.31377165 0.97032094 938.58622 20000 1 -0.44719826 0 0.23916537 1.0118322 936.68972 21000 1 -0.39518804 0 0.29117559 1.0584198 935.59526 22000 1 -0.36368989 0 0.32267374 1.0593392 935.25352 23000 1 -0.41084354 0 0.27552009 0.9952792 936.90123 24000 1 -0.39025763 0 0.29610601 1.014413 941.44567 25000 1 -0.36909647 0 0.31726717 0.9812463 940.90255 Loop time of 4.94495 on 4 procs for 25000 steps with 770 atoms Pair time (%) = 0.416176 (8.41618) Neigh time (%) = 0.147718 (2.98725) Comm time (%) = 2.01956 (40.8409) Outpt time (%) = 0.358058 (7.24087) Other time (%) = 2.00344 (40.5148) Nlocal: 192.5 ave 240 max 158 min Histogram: 2 0 0 0 0 1 0 0 0 1 Nghost: 42.5 ave 45 max 37 min Histogram: 1 0 0 0 0 0 0 0 2 1 Neighs: 401.25 ave 559 max 288 min Histogram: 2 0 0 0 0 0 1 0 0 1 Total # of neighbors = 1605 Ave neighs/atom = 2.08442 Neighbor list builds = 1636 Dangerous builds = 0