LAMMPS (7 Jul 2009) # 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) 1 by 1 by 1 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 # Run timestep 0.0025 thermo 1000 thermo_modify temp new dump 1 all atom 500 dump.friction run 20000 Memory usage per processor = 1.73539 Mbytes Step Temp E_pair E_mol TotEng Press Volume 0 0.1 -3.1333672 0 -3.0921259 -1.1440102 2444.4558 1000 0.1 -3.0915465 0 -3.0503052 0.010017516 2444.4558 2000 0.1 -3.0826487 0 -3.0414074 -0.42021097 2444.4558 3000 0.089819692 -3.07584 0 -3.0387972 -0.25257042 2444.4558 4000 0.098489874 -3.0667093 0 -3.0260907 -0.25511521 2444.4558 5000 0.11379986 -3.0557087 0 -3.0087762 -0.080886978 2444.4558 6000 0.11269179 -3.04532 0 -2.9988445 -0.33387724 2444.4558 7000 0.1 -3.0380598 0 -2.9968185 -0.32430283 2444.4558 8000 0.1 -3.0346457 0 -2.9934044 -0.38023276 2444.4558 9000 0.1 -3.0327792 0 -2.9915379 -0.43204961 2444.4558 10000 0.11908329 -3.0384756 0 -2.9893641 -0.34377218 2444.4558 11000 0.1 -3.0307666 0 -2.9895253 -0.46039249 2444.4558 12000 0.11748666 -3.0410033 0 -2.9925503 -0.21956005 2444.4558 13000 0.1 -3.0416003 0 -3.000359 -0.3651589 2444.4558 14000 0.11069381 -3.0439855 0 -2.998334 -0.28704457 2444.4558 15000 0.11218605 -3.0480708 0 -3.0018038 -0.32666261 2444.4558 16000 0.11189162 -3.0483127 0 -3.0021671 -0.23171462 2444.4558 17000 0.11423906 -3.0474938 0 -3.0003802 -0.34260897 2444.4558 18000 0.11548632 -3.047828 0 -3.0002 -0.31060102 2444.4558 19000 0.10034246 -3.0488263 0 -3.0074438 -0.2527683 2444.4558 20000 0.10505024 -3.0494404 0 -3.0061164 -0.31791192 2444.4558 Loop time of 10.8242 on 1 procs for 20000 steps with 1724 atoms Pair time (%) = 9.04606 (83.5728) Neigh time (%) = 0.446001 (4.12042) Comm time (%) = 0.0695286 (0.642346) Outpt time (%) = 0.105748 (0.976966) Other time (%) = 1.15683 (10.6875) Nlocal: 1724 ave 1724 max 1724 min Histogram: 1 0 0 0 0 0 0 0 0 0 Nghost: 146 ave 146 max 146 min Histogram: 1 0 0 0 0 0 0 0 0 0 Neighs: 14389 ave 14389 max 14389 min Histogram: 1 0 0 0 0 0 0 0 0 0 Total # of neighbors = 14389 Ave neighs/atom = 8.34629 Neighbor list builds = 723 Dangerous builds = 0