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) 1 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 = 2.06342 Mbytes Step Temp E_pair E_mol TotEng Press Volume 0 1.0027471 0 0 0.68849216 0.463265 1142.8674 1000 1 -0.33689286 0 0.34971312 1.2907615 1286.5545 2000 1 -0.36746164 0 0.31914434 1.1670767 1313.2217 3000 1 -0.52004751 0 0.16655848 1.4180076 1324.2707 4000 1 -0.50683859 0 0.17976739 1.4853867 1370.6777 5000 1 -0.49212307 0 0.19448291 1.2865932 1411.3324 6000 1 -0.45795739 0 0.22864859 1.242781 1441.6839 7000 1 -0.443252 0 0.24335398 1.2417302 1445.4704 8000 1 -0.37679433 0 0.30981165 1.1957462 1448.9419 9000 1 -0.41492237 0 0.27168361 1.0747045 1450.089 10000 1 -0.40197739 0 0.28462859 1.0279259 1456.1397 11000 1 -0.43056157 0 0.25604441 1.0722172 1449.4829 12000 1 -0.41156343 0 0.27504255 1.1499381 1452.9273 13000 1 -0.41466957 0 0.27193641 1.0548151 1455.565 14000 1 -0.41349951 0 0.27310647 1.0064325 1459.8774 15000 1 -0.4058151 0 0.28079088 0.96339054 1459.8033 16000 1 -0.37996671 0 0.30663928 1.0352366 1455.9433 17000 1 -0.35238448 0 0.3342215 0.94045311 1467.1239 18000 1 -0.39054272 0 0.29606326 1.0575731 1462.7124 19000 1 -0.36310964 0 0.32349634 0.97451832 1467.3645 20000 1 -0.37725444 0 0.30935154 0.98660138 1461.9506 21000 1 -0.37974771 0 0.30685827 0.94488958 1460.4569 22000 1 -0.35523952 0 0.33136646 1.0169815 1461.2727 23000 1 -0.36389429 0 0.32271169 1.0120096 1467.6367 24000 1 -0.40916195 0 0.27744403 0.95800623 1463.0811 25000 1 -0.39382698 0 0.292779 0.95226646 1460.6167 Loop time of 1.79053 on 1 procs for 25000 steps with 769 atoms Pair time (%) = 0.497143 (27.7651) Neigh time (%) = 0.13512 (7.54639) Comm time (%) = 0.0265169 (1.48095) Outpt time (%) = 0.147151 (8.21829) Other time (%) = 0.984599 (54.9892) Nlocal: 769 ave 769 max 769 min Histogram: 1 0 0 0 0 0 0 0 0 0 Nghost: 44 ave 44 max 44 min Histogram: 1 0 0 0 0 0 0 0 0 0 Neighs: 1647 ave 1647 max 1647 min Histogram: 1 0 0 0 0 0 0 0 0 0 Total # of neighbors = 1647 Ave neighs/atom = 2.14174 Neighbor list builds = 1647 Dangerous builds = 0