LAMMPS (5 Oct 2016) # 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 MPI 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 # Poiseuille 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 WARNING: Temperature for thermo pressure is not for group all (../thermo.cpp:474) #dump 1 all atom 500 dump.flow #dump 2 all image 100 image.*.jpg type type # zoom 1.6 adiam 1.2 #dump_modify 2 pad 5 #dump 3 all movie 100 movie.mpg type type # zoom 1.6 adiam 1.2 #dump_modify 3 pad 5 run 10000 Neighbor list info ... 1 neighbor list requests update every 1 steps, delay 5 steps, check yes max neighbors/atom: 2000, page size: 100000 master list distance cutoff = 1.42246 ghost atom cutoff = 1.42246 binsize = 0.71123 -> bins = 37 32 1 Memory usage per processor = 2.47768 Mbytes Step Temp E_pair E_mol TotEng Press Volume 0 1 0 0 0.71190476 0.52314537 571.54286 500 1.0951876 -0.33403931 0 0.44562996 3.2502319 571.54286 1000 1 -0.3731019 0 0.33880286 2.8561715 571.54286 1500 1.0366879 -0.36031105 0 0.37771198 3.0196355 571.54286 2000 1 -0.41052999 0 0.30137477 2.865191 571.54286 2500 1.1227078 -0.37036396 0 0.42889708 2.944809 571.54286 3000 1 -0.3831188 0 0.32878596 2.6840526 571.54286 3500 1.0822111 -0.42234615 0 0.34808509 2.8119594 571.54286 4000 1 -0.40805417 0 0.30385059 2.5977913 571.54286 4500 1.0910738 -0.37103658 0 0.40570404 2.3742519 571.54286 5000 1 -0.46702664 0 0.24487812 2.5666252 571.54286 5500 1.0411533 -0.40531814 0 0.33588386 2.5125963 571.54286 6000 1 -0.36183137 0 0.35007339 2.4382625 571.54286 6500 1.0533061 -0.38887062 0 0.360983 2.6032319 571.54286 7000 1 -0.49087253 0 0.22103223 2.4362009 571.54286 7500 1.056871 -0.42142263 0 0.33096887 2.5406254 571.54286 8000 1 -0.40440166 0 0.3075031 2.3664523 571.54286 8500 1.0340789 -0.36193981 0 0.37422586 2.4461942 571.54286 9000 1 -0.45171969 0 0.26018507 2.5525861 571.54286 9500 1.0322994 -0.40989898 0 0.32499991 2.6021234 571.54286 10000 1 -0.42489516 0 0.28700961 2.619505 571.54286 Loop time of 0.134939 on 4 procs for 10000 steps with 420 atoms Performance: 19208643.416 tau/day, 74107.421 timesteps/s 99.3% CPU use with 4 MPI tasks x no OpenMP threads MPI task timing breakdown: Section | min time | avg time | max time |%varavg| %total --------------------------------------------------------------- Pair | 0.024453 | 0.030829 | 0.036954 | 3.5 | 22.85 Neigh | 0.0152 | 0.016832 | 0.018415 | 1.2 | 12.47 Comm | 0.040894 | 0.049385 | 0.058308 | 3.7 | 36.60 Output | 0.00027037 | 0.00029039 | 0.0003438 | 0.2 | 0.22 Modify | 0.017885 | 0.018734 | 0.019774 | 0.6 | 13.88 Other | | 0.01887 | | | 13.98 Nlocal: 105 ave 113 max 97 min Histogram: 2 0 0 0 0 0 0 0 0 2 Nghost: 39.5 ave 43 max 36 min Histogram: 1 0 0 0 1 1 0 0 0 1 Neighs: 236.75 ave 287 max 183 min Histogram: 2 0 0 0 0 0 0 0 0 2 Total # of neighbors = 947 Ave neighs/atom = 2.25476 Neighbor list builds = 966 Dangerous builds = 0 Total wall time: 0:00:00