LAMMPS (5 Oct 2016) # 2d friction simulation dimension 2 boundary p s p atom_style atomic neighbor 0.3 bin neigh_modify delay 5 # create geometry lattice hex 0.9 Lattice spacing in x,y,z = 1.1327 1.96189 1.1327 region box block 0 50 0 22 -0.25 0.25 create_box 4 box Created orthogonal box = (0 0 -0.283174) to (56.6348 43.1615 0.283174) 2 by 2 by 1 MPI processor grid mass 1 1.0 mass 2 1.0 mass 3 1.0 mass 4 1.0 # atom regions region lo-fixed block INF INF INF 1.1 INF INF region lo-slab block INF INF INF 7 INF INF region above-lo block INF INF INF 7 INF INF side out region hi-fixed block INF INF 20.9 INF INF INF region hi-slab block INF INF 15 INF INF INF region below-hi block INF INF 15 INF INF INF side out region lo-asperity sphere 32 7 0 8 region hi-asperity sphere 18 15 0 8 region lo-half-sphere intersect 2 lo-asperity above-lo region hi-half-sphere intersect 2 hi-asperity below-hi # create 2 surfaces with asperities create_atoms 1 region lo-slab Created 750 atoms create_atoms 1 region hi-slab Created 750 atoms create_atoms 2 region lo-half-sphere Created 112 atoms create_atoms 3 region hi-half-sphere Created 112 atoms # LJ potentials pair_style lj/cut 2.5 pair_coeff * * 1.0 1.0 2.5 # define groups group lo region lo-slab 750 atoms in group lo group lo type 2 862 atoms in group lo group hi region hi-slab 750 atoms in group hi group hi type 3 862 atoms in group hi group lo-fixed region lo-fixed 150 atoms in group lo-fixed group hi-fixed region hi-fixed 150 atoms in group hi-fixed group boundary union lo-fixed hi-fixed 300 atoms in group boundary group mobile subtract all boundary 1424 atoms in group mobile set group lo-fixed type 4 150 settings made for type set group hi-fixed type 4 150 settings made for type # initial velocities compute new mobile temp/partial 0 1 0 velocity mobile create 0.1 482748 temp new velocity hi set 1.0 0.0 0.0 sum yes # fixes fix 1 all nve fix 2 boundary setforce 0.0 0.0 0.0 fix 3 mobile temp/rescale 200 0.1 0.1 0.02 1.0 fix_modify 3 temp new fix 4 all enforce2d # Run timestep 0.0025 thermo 1000 thermo_modify temp new WARNING: Temperature for thermo pressure is not for group all (../thermo.cpp:474) #dump 1 all atom 500 dump.friction #dump 2 all image 500 image.*.jpg type type # zoom 1.6 adiam 1.5 #dump_modify 2 pad 5 #dump 3 all movie 500 movie.mpg type type # zoom 1.6 adiam 1.5 #dump_modify 3 pad 5 run 20000 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 = 2.8 ghost atom cutoff = 2.8 binsize = 1.4 -> bins = 41 31 1 Memory usage per processor = 2.47775 Mbytes Step Temp E_pair E_mol TotEng Press Volume 0 0.1 -3.1333672 0 -3.0920969 -1.1437663 2444.9333 1000 0.081947197 -3.0926906 0 -3.0588707 -0.021905504 2444.9333 2000 0.082643627 -3.0850391 0 -3.0509318 -0.44951926 2444.9333 3000 0.09228068 -3.0747307 0 -3.0366461 -0.25332113 2444.9333 4000 0.096009906 -3.0564001 0 -3.0167765 -0.026756079 2444.9333 5000 0.11991393 -3.0463606 0 -2.9968718 -0.095571711 2444.9333 6000 0.11344201 -3.0428779 0 -2.9960601 -0.28750906 2444.9333 7000 0.11932053 -3.0297394 0 -2.9804955 -0.44411602 2444.9333 8000 0.11472412 -3.0260173 0 -2.9786703 -0.45505281 2444.9333 9000 0.1153823 -3.0172996 0 -2.969681 -0.54699367 2444.9333 10000 0.1110096 -3.0180324 0 -2.9722184 -0.28712224 2444.9333 11000 0.10553488 -3.0281386 0 -2.984584 -0.40414683 2444.9333 12000 0.10913279 -3.0339553 0 -2.9889159 -0.23876138 2444.9333 13000 0.10791089 -3.036479 0 -2.9919439 -0.4066437 2444.9333 14000 0.11089726 -3.0434547 0 -2.9976871 -0.25931118 2444.9333 15000 0.10791244 -3.0452052 0 -3.0006694 -0.31309363 2444.9333 16000 0.11451836 -3.0490643 0 -3.0018023 -0.28317436 2444.9333 17000 0.10861713 -3.044417 0 -2.9995904 -0.39120148 2444.9333 18000 0.11086121 -3.0462098 0 -3.0004571 -0.19272619 2444.9333 19000 0.11407977 -3.046791 0 -2.99971 -0.29824356 2444.9333 20000 0.11532037 -3.0463959 0 -2.9988028 -0.3435294 2444.9333 Loop time of 1.90668 on 4 procs for 20000 steps with 1724 atoms Performance: 2265719.994 tau/day, 10489.444 timesteps/s 99.4% CPU use with 4 MPI tasks x no OpenMP threads MPI task timing breakdown: Section | min time | avg time | max time |%varavg| %total --------------------------------------------------------------- Pair | 1.0349 | 1.1944 | 1.3574 | 10.5 | 62.64 Neigh | 0.070767 | 0.082252 | 0.094675 | 3.0 | 4.31 Comm | 0.19432 | 0.3776 | 0.54764 | 20.4 | 19.80 Output | 0.00043559 | 0.00045842 | 0.00052333 | 0.2 | 0.02 Modify | 0.12252 | 0.14002 | 0.15438 | 3.1 | 7.34 Other | | 0.112 | | | 5.87 Nlocal: 431 ave 479 max 377 min Histogram: 1 1 0 0 0 0 0 0 0 2 Nghost: 99.25 ave 120 max 81 min Histogram: 1 1 0 0 0 0 1 0 0 1 Neighs: 3597 ave 4064 max 3146 min Histogram: 2 0 0 0 0 0 0 0 0 2 Total # of neighbors = 14388 Ave neighs/atom = 8.34571 Neighbor list builds = 717 Dangerous builds = 0 Total wall time: 0:00:01