LAMMPS (1 Feb 2014) # sample LAMMPS input script for viscosity of 2d LJ liquid # Muller-Plathe via fix viscosity # settings variable x equal 20 variable y equal 20 variable rho equal 0.6 variable t equal 1.0 variable rc equal 2.5 # problem setup units lj dimension 2 atom_style atomic neigh_modify delay 0 every 1 lattice sq2 ${rho} lattice sq2 0.6 Lattice spacing in x,y,z = 1.82574 1.82574 1.82574 region simbox block 0 $x 0 $y -0.1 0.1 region simbox block 0 20 0 $y -0.1 0.1 region simbox block 0 20 0 20 -0.1 0.1 create_box 1 simbox Created orthogonal box = (0 0 -0.182574) to (36.5148 36.5148 0.182574) 1 by 1 by 1 MPI processor grid create_atoms 1 box Created 800 atoms pair_style lj/cut ${rc} pair_style lj/cut 2.5 pair_coeff * * 1 1 mass * 1.0 velocity all create $t 97287 velocity all create 1 97287 fix 1 all nve fix 2 all langevin $t $t 0.1 498094 fix 2 all langevin 1 $t 0.1 498094 fix 2 all langevin 1 1 0.1 498094 fix 3 all enforce2d # equilibration run thermo 1000 run 5000 Memory usage per processor = 2.06394 Mbytes Step Temp E_pair E_mol TotEng Press 0 1 -1.56492 0 -0.56617 -1.535262 1000 0.95906897 -1.571142 0 -0.61327189 0.82593948 2000 1.0164992 -1.6006146 0 -0.58538603 0.88642098 3000 1.0429232 -1.5801639 0 -0.53854441 1.157286 4000 1.0955206 -1.6156387 0 -0.52148756 0.94410568 5000 0.94117593 -1.6155055 0 -0.67550602 0.79354126 Loop time of 0.858331 on 1 procs for 5000 steps with 800 atoms Pair time (%) = 0.46184 (53.8067) Neigh time (%) = 0.102345 (11.9237) Comm time (%) = 0.0174992 (2.03875) Outpt time (%) = 5.10216e-05 (0.00594428) Other time (%) = 0.276596 (32.2248) Nlocal: 800 ave 800 max 800 min Histogram: 1 0 0 0 0 0 0 0 0 0 Nghost: 256 ave 256 max 256 min Histogram: 1 0 0 0 0 0 0 0 0 0 Neighs: 5583 ave 5583 max 5583 min Histogram: 1 0 0 0 0 0 0 0 0 0 Total # of neighbors = 5583 Ave neighs/atom = 6.97875 Neighbor list builds = 551 Dangerous builds = 0 unfix 2 # turn on Muller-Plathe driving force and equilibrate some more velocity all scale $t velocity all scale 1 fix 4 all viscosity 100 x y 20 fix 5 all ave/spatial 20 50 1000 y center 0.05 vx units reduced file profile.mp.2d # equilibration run variable dVx equal f_5[11][3]-f_5[1][3] thermo 1000 thermo_style custom step temp epair etotal press f_4 v_dVx run 20000 WARNING: Fix viscosity comes before fix ave/spatial (../fix_viscosity.cpp:129) Memory usage per processor = 2.06486 Mbytes Step Temp E_pair TotEng Press 4 dVx 5000 1 -1.6155055 -0.61675549 0.82879159 0 0 6000 0.98687509 -1.6019556 -0.6163141 0.81812957 -40.544054 0.48107738 7000 0.99812635 -1.61413 -0.6172513 0.88049928 -72.131982 0.83982485 8000 0.99508548 -1.6108778 -0.61703621 1.0010053 -105.28099 0.80829601 9000 0.94912106 -1.564488 -0.61655333 1.0184324 -141.59349 0.94800981 10000 0.99258056 -1.6078678 -0.61652794 0.94564321 -171.73806 1.1494339 11000 1.0159215 -1.6317434 -0.61709181 0.92235272 -199.00526 1.1830449 12000 1.0126611 -1.6277928 -0.61639754 0.7688915 -227.93583 1.2636885 13000 1.0122947 -1.6285623 -0.61753296 0.88334788 -258.44565 1.217365 14000 1.0175562 -1.6335087 -0.61722444 0.84125493 -282.91095 1.3683789 15000 0.97750561 -1.5930807 -0.61679697 1.1287326 -313.39632 1.2230677 16000 0.98242425 -1.5980008 -0.61680456 0.91325299 -339.83912 1.2882183 17000 1.008242 -1.6242405 -0.61725887 0.87284759 -365.79175 1.4803679 18000 0.99455824 -1.610205 -0.61688999 0.80190574 -391.57365 1.3145093 19000 1.0075504 -1.6245154 -0.61822443 1.1173911 -419.47456 1.2444018 20000 1.0169723 -1.6334224 -0.6177213 0.8584711 -448.67177 1.2101637 21000 0.98967224 -1.6055692 -0.61713404 0.80442505 -476.9284 1.4306147 22000 0.97813764 -1.5935756 -0.61666068 0.99668957 -501.83621 1.5824584 23000 0.98098823 -1.5963749 -0.61661287 1.1169304 -526.25935 1.4837827 24000 1.0002987 -1.6158635 -0.61681517 0.92338935 -554.31346 1.3408732 25000 0.99862734 -1.6139679 -0.61658884 0.87430158 -582.99367 1.2441321 Loop time of 2.75452 on 1 procs for 20000 steps with 800 atoms Pair time (%) = 1.86056 (67.5458) Neigh time (%) = 0.440814 (16.0033) Comm time (%) = 0.0745592 (2.7068) Outpt time (%) = 0.000242233 (0.00879403) Other time (%) = 0.378341 (13.7353) Nlocal: 800 ave 800 max 800 min Histogram: 1 0 0 0 0 0 0 0 0 0 Nghost: 253 ave 253 max 253 min Histogram: 1 0 0 0 0 0 0 0 0 0 Neighs: 5598 ave 5598 max 5598 min Histogram: 1 0 0 0 0 0 0 0 0 0 Total # of neighbors = 5598 Ave neighs/atom = 6.9975 Neighbor list builds = 2354 Dangerous builds = 0 # data gathering run # reset fix viscosity to zero flux accumulation unfix 4 fix 4 all viscosity 100 x y 20 variable visc equal -(f_4/(2*(step*0.005-125)*lx+1.0e-10))/(v_dVx/(ly/2)) fix vave all ave/time 1000 1 1000 v_visc ave running start 26000 thermo_style custom step temp f_4 v_dVx v_visc f_vave # only need to run for 10000 steps to make a good 100-frame movie #dump 1 all custom 100 dump.mp.2d id type x y z vx #dump 1 all image 100 image.*.jpg vx type zoom 1.6 adiam 1.2 #dump_modify 1 pad 5 amap -0.7 0.7 ca 0.0 2 min blue max red run 50000 Memory usage per processor = 2.103 Mbytes Step Temp 4 dVx visc vave 25000 0.99862734 0 1.2441321 0 0 26000 1.006121 -29.834985 1.0067717 1.4817155 0.74085773 27000 1.000685 -57.28656 1.3703643 1.0450973 0.84227093 28000 1.0119383 -82.689969 1.5329066 0.8990542 0.85646674 29000 1.005591 -111.52398 1.3679394 1.0190874 0.88899088 30000 0.9780793 -132.09122 1.4693711 0.89896428 0.89065311 31000 0.98954223 -160.54318 1.4144949 0.94582162 0.89853433 32000 0.98452695 -186.95511 1.3592447 0.9824527 0.90902412 33000 1.0137305 -216.75823 1.1667402 1.1611316 0.93703607 34000 1.004699 -243.79453 1.3554751 0.99921723 0.94325418 35000 0.99279233 -272.99034 1.4414031 0.94696042 0.94359111 36000 0.98601686 -296.44885 1.2290954 1.0963305 0.9563194 37000 0.99960393 -327.77258 1.2754827 1.0707469 0.96512151 38000 1.0232092 -354.20371 1.471032 0.92609943 0.96233422 39000 1.0220897 -380.33308 1.4729611 0.92217809 0.95965714 40000 1.003192 -409.96551 1.1486002 1.189754 0.9740382 41000 1.0339239 -441.2471 1.2766924 1.0800543 0.98027444 42000 0.9707256 -469.29726 1.298219 1.0632151 0.98488226 43000 1.012508 -498.86351 1.3419554 1.0326215 0.98739485 44000 1.0104362 -528.29202 1.2868256 1.0803656 0.99204339 45000 1.0031694 -554.14027 1.3431643 1.0314082 0.9939179 46000 0.98757964 -582.17026 1.3410473 1.0336098 0.99572208 47000 1.0329913 -612.8052 1.0693478 1.3024192 1.0090567 48000 1.0040957 -640.38 1.3648753 1.0199689 1.0095114 49000 1.0213711 -667.39045 1.3779353 1.0090436 1.0094927 50000 1.0028765 -693.00523 1.353182 1.0242602 1.0100607 51000 1.0456929 -723.75516 1.3013825 1.0695063 1.0122624 52000 0.98661701 -753.9132 1.1752559 1.1879417 1.0185366 53000 1.0067127 -785.13019 1.0304513 1.3605866 1.0303315 54000 1.0049746 -814.24066 1.3688029 1.0256138 1.0301742 55000 0.99145341 -839.02294 1.5370182 0.90979505 1.026291 56000 0.99330997 -866.91329 1.4290157 0.9784688 1.0247966 57000 0.97297071 -891.05513 1.3697724 1.016427 1.0245429 58000 1.0055628 -915.32616 1.7035058 0.81411979 1.018354 59000 0.97447836 -940.88078 1.4544592 0.95131452 1.0164386 60000 0.97786144 -970.22273 1.3938314 0.99440472 1.0158266 61000 1.0069781 -996.52024 1.2925348 1.0708074 1.0173125 62000 0.99860063 -1024.4668 1.3677043 1.0122178 1.0171785 63000 1.0160002 -1052.8951 1.2909807 1.0731286 1.0186131 64000 1.0075017 -1081.0833 1.4389443 0.96320906 1.017228 65000 1.0128103 -1110.5507 1.3712762 1.0123332 1.0171086 66000 0.99788687 -1138.143 1.1744686 1.1817934 1.0210297 67000 0.99340723 -1165.3818 1.2141024 1.1427037 1.0238593 68000 0.99891442 -1194.3011 1.1838074 1.1730981 1.0272511 69000 1.010782 -1222.8307 1.2890796 1.0779631 1.028378 70000 1.0084059 -1254.3924 1.3961366 0.99830441 1.0277242 71000 0.98457274 -1285.1565 1.3228471 1.055987 1.0283256 72000 0.98997963 -1309.8959 1.3420552 1.0383376 1.0285342 73000 0.99661456 -1338.2166 1.114478 1.2507878 1.0330699 74000 0.98823959 -1367.5535 1.1382114 1.2260136 1.0369288 75000 0.99114295 -1396.3043 1.181084 1.1822226 1.0397777 Loop time of 6.87975 on 1 procs for 50000 steps with 800 atoms Pair time (%) = 4.64786 (67.5585) Neigh time (%) = 1.09953 (15.9821) Comm time (%) = 0.184543 (2.68241) Outpt time (%) = 0.000693083 (0.0100742) Other time (%) = 0.947126 (13.7669) Nlocal: 800 ave 800 max 800 min Histogram: 1 0 0 0 0 0 0 0 0 0 Nghost: 257 ave 257 max 257 min Histogram: 1 0 0 0 0 0 0 0 0 0 Neighs: 5559 ave 5559 max 5559 min Histogram: 1 0 0 0 0 0 0 0 0 0 Total # of neighbors = 5559 Ave neighs/atom = 6.94875 Neighbor list builds = 5873 Dangerous builds = 0