LAMMPS (22 Jan 2008) # 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 -3.0921549 -1.1440307 2444.4558 1000 0.085622556 -3.0583969 0 -3.0231098 0.033995503 2444.4558 2000 0.085921887 -3.0572271 0 -3.0218167 -0.51378547 2444.4558 3000 0.10739474 -3.0650606 0 -3.0208008 -0.035547438 2444.4558 4000 0.089682132 -3.04809 0 -3.01113 -0.19064505 2444.4558 5000 0.10934102 -3.0485926 0 -3.0035307 0.1034494 2444.4558 6000 0.10817011 -3.0584907 0 -3.0139113 -0.31026241 2444.4558 7000 0.10519386 -3.0511555 0 -3.0078027 -0.23777457 2444.4558 8000 0.11660726 -3.0348032 0 -2.9867467 -0.40191693 2444.4558 9000 0.1 -3.0308538 0 -2.9896415 -0.30056676 2444.4558 10000 0.10422874 -3.0468394 0 -3.0038843 -0.41010239 2444.4558 11000 0.10907653 -3.0470568 0 -3.0021038 -0.39779677 2444.4558 12000 0.10518096 -3.0467458 0 -3.0033983 -0.28073637 2444.4558 13000 0.1052846 -3.0424889 0 -2.9990987 -0.39335018 2444.4558 14000 0.10942544 -3.0462295 0 -3.0011328 -0.31177088 2444.4558 15000 0.10696705 -3.0423514 0 -2.9982679 -0.39759929 2444.4558 16000 0.11637773 -3.0496752 0 -3.0017132 -0.19541362 2444.4558 17000 0.11090878 -3.0452336 0 -2.9995256 -0.41097653 2444.4558 18000 0.11274493 -3.0471847 0 -3.0007199 -0.31516775 2444.4558 19000 0.1058703 -3.0463493 0 -3.0027177 -0.28413841 2444.4558 20000 0.11224126 -3.0475136 0 -3.0012564 -0.24520009 2444.4558 Loop time of 10.8085 on 1 procs for 20000 steps with 1724 atoms Pair time (%) = 9.04044 (83.642) Neigh time (%) = 0.445875 (4.12523) Comm time (%) = 0.0687661 (0.636223) Outpt time (%) = 0.096189 (0.889939) Other time (%) = 1.15723 (10.7067) Nlocal: 1724 ave 1724 max 1724 min Histogram: 1 0 0 0 0 0 0 0 0 0 Nghost: 142 ave 142 max 142 min Histogram: 1 0 0 0 0 0 0 0 0 0 Neighs: 14388 ave 14388 max 14388 min Histogram: 1 0 0 0 0 0 0 0 0 0 Total # of neighbors = 14388 Ave neighs/atom = 8.34571 Neighbor list builds = 736 Dangerous builds = 0