LAMMPS (21 Nov 2023 - Development - patch_21Nov2023-665-g17f869bf5e) OMP_NUM_THREADS environment is not set. Defaulting to 1 thread. (src/comm.cpp:98) using 1 OpenMP thread(s) per MPI task # SRD viscosity demo - dimer particles units lj atom_style sphere atom_modify map array first big dimension 2 # read in clusters of rigid bodies fix molprop all property/atom mol ghost yes read_data data.dimer fix molprop NULL Molecules Reading data file ... orthogonal box = (-9.341652 -9.341652 -0.5) to (9.341652 9.341652 0.5) 2 by 2 by 1 MPI processor grid reading atoms ... 200 atoms read_data CPU = 0.001 seconds set type 1 mass 1.0 Setting atom values ... 200 settings made for mass group big type 1 200 atoms in group big velocity big create 1.44 87287 loop geom # equilibrate big particles pair_style soft 1.12 pair_coeff 1 1 0.0 pair_coeff 2 2 0.0 0.0 pair_coeff 1 2 0.0 0.0 variable prefactor equal ramp(0,60) fix soft all adapt 1 pair soft a * * v_prefactor fix 1 big rigid molecule 100 rigid bodies with 200 atoms fix 2 all enforce2d #dump 1 all atom 10 dump.dimer.equil thermo 100 run 1000 Generated 0 of 1 mixed pair_coeff terms from geometric mixing rule Neighbor list info ... update: every = 1 steps, delay = 0 steps, check = yes max neighbors/atom: 2000, page size: 100000 master list distance cutoff = 1.42 ghost atom cutoff = 1.42 binsize = 0.71, bins = 27 27 2 1 neighbor lists, perpetual/occasional/extra = 1 0 0 (1) pair soft, perpetual attributes: half, newton on pair build: half/bin/atomonly/newton stencil: half/bin/2d bin: standard Per MPI rank memory allocation (min/avg/max) = 5.553 | 5.553 | 5.553 Mbytes Step Temp E_pair E_mol TotEng Press 0 3.4028231 0 0 0.83369167 -0.55065517 100 9.5167872 2.392105 0 4.7237178 2.8319556 200 13.564465 3.0352634 0 6.3585572 3.6388732 300 13.133051 4.3835112 0 7.6011086 4.060051 400 14.576837 5.5141059 0 9.0854309 4.422762 500 15.227825 6.6472106 0 10.378028 4.8598912 600 16.93219 7.454865 0 11.603251 5.2908894 700 16.573769 8.7323442 0 12.792918 5.3544684 800 17.482599 9.7221047 0 14.005341 5.6200973 900 18.548144 10.739353 0 15.283649 4.7817995 1000 18.068079 12.058417 0 16.485096 6.5773093 Loop time of 0.0421376 on 4 procs for 1000 steps with 200 atoms Performance: 10252121.014 tau/day, 23731.762 timesteps/s, 4.746 Matom-step/s 99.2% CPU use with 4 MPI tasks x 1 OpenMP threads MPI task timing breakdown: Section | min time | avg time | max time |%varavg| %total --------------------------------------------------------------- Pair | 0.002222 | 0.0023177 | 0.0024199 | 0.2 | 5.50 Neigh | 0.0010943 | 0.0011428 | 0.001174 | 0.1 | 2.71 Comm | 0.0097533 | 0.009878 | 0.010001 | 0.1 | 23.44 Output | 9.4323e-05 | 0.0001028 | 0.00012783 | 0.0 | 0.24 Modify | 0.02557 | 0.026225 | 0.026638 | 0.3 | 62.24 Other | | 0.002471 | | | 5.86 Nlocal: 50 ave 55 max 47 min Histogram: 2 0 0 0 0 1 0 0 0 1 Nghost: 33.75 ave 38 max 32 min Histogram: 2 1 0 0 0 0 0 0 0 1 Neighs: 68.75 ave 77 max 64 min Histogram: 2 0 0 1 0 0 0 0 0 1 Total # of neighbors = 275 Ave neighs/atom = 1.375 Neighbor list builds = 193 Dangerous builds = 0 #undump 1 unfix soft unfix 1 unfix 2 # add small particles as hi density lattice region plane block INF INF INF INF -0.001 0.001 units box lattice sq 85.0 Lattice spacing in x,y,z = 0.10846523 0.10846523 0.10846523 create_atoms 2 region plane Created 29929 atoms using lattice units in orthogonal box = (-9.341652 -9.341652 -0.5) to (9.341652 9.341652 0.5) create_atoms CPU = 0.002 seconds set type 2 mass 0.1 Setting atom values ... 29929 settings made for mass group small type 2 29929 atoms in group small velocity small create 1.0 593849 loop geom # delete overlaps # must set 1-2 cutoff to non-zero value pair_style lj/cut 2.5 pair_coeff 1 1 1.0 1.0 pair_coeff 2 2 0.0 1.0 0.0 pair_coeff 1 2 0.0 1.0 0.5 delete_atoms overlap 0.5 small big System init for delete_atoms ... Generated 0 of 1 mixed pair_coeff terms from geometric mixing rule Neighbor list info ... update: every = 1 steps, delay = 0 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 = 14 14 1 2 neighbor lists, perpetual/occasional/extra = 1 1 0 (1) command delete_atoms, occasional attributes: full, newton on pair build: full/bin/atomonly stencil: full/bin/2d bin: standard (2) pair lj/cut, perpetual attributes: half, newton on pair build: half/bin/atomonly/newton stencil: half/bin/2d bin: standard WARNING: Delete_atoms cutoff > minimum neighbor cutoff (src/delete_atoms.cpp:312) Deleted 12776 atoms, new total = 17353 # SRD run reset_timestep 0 neighbor 0.3 multi neigh_modify delay 0 every 1 check yes comm_modify mode multi group big vel yes neigh_modify include big # no pairwise interactions with small particles pair_style lj/cut 2.5 pair_coeff 1 1 1.0 1.0 pair_coeff 2 2 0.0 1.0 0.0 pair_coeff 1 2 0.0 1.0 0.0 # use fix SRD to push small particles out from inside big ones # if comment out, big particles won't see SRD particles timestep 0.001 fix 1 big rigid molecule 100 rigid bodies with 200 atoms fix 2 small srd 20 big 1.0 0.25 49894 shift yes 54979 search 0.2 collision slip inside ignore overlap yes fix 3 small viscosity 10 x y 50 fix 4 all enforce2d # diagnostics compute tbig big temp/sphere variable pebig equal pe*atoms/count(big) variable ebig equal etotal*atoms/count(big) thermo_style custom step temp f_2[8] etotal v_pebig v_ebig press f_2[1] f_2[2] f_2[3] f_2[4] f_2[5] f_2[6] f_2[7] f_2[8] f_2[9] f_2[10] f_2[11] f_2[12] thermo_modify temp tbig WARNING: Temperature for thermo pressure is not for group all (src/thermo.cpp:530) thermo 1000 #dump 1 all atom 500 dump.dimer.mp #dump 1 all image 500 image.*.jpg type type zoom 1.6 #dump_modify 1 pad 6 adiam 1 1 adiam 2 0.2 run 25000 CITE-CITE-CITE-CITE-CITE-CITE-CITE-CITE-CITE-CITE-CITE-CITE-CITE Your simulation uses code contributions which should be cited: - neighbor multi command: doi:10.1016/j.cpc.2008.03.005, doi:10.1007/s40571-020-00361-2 @Article{Intveld08, author = {in 't Veld, P. J. and S. J.~Plimpton and G. S. Grest}, title = {Accurate and Efficient Methods for Modeling Colloidal Mixtures in an Explicit Solvent using Molecular Dynamics}, journal = {Comput.\ Phys.\ Commut.}, year = 2008, volume = 179, pages = {320--329} } @article{Shire2020, author = {Shire, Tom and Hanley, Kevin J. and Stratford, Kevin}, title = {{DEM} Simulations of Polydisperse Media: Efficient Contact Detection Applied to Investigate the Quasi-Static Limit}, journal = {Computational Particle Mechanics}, year = {2020} @article{Monti2022, author = {Monti, Joseph M. and Clemmer, Joel T. and Srivastava, Ishan and Silbert, Leonardo E. and Grest, Gary S. and Lechman, Jeremy B.}, title = {Large-scale frictionless jamming with power-law particle size distributions}, journal = {Phys. Rev. E}, volume = {106} issue = {3} year = {2022} } - fix srd command: doi:10.1063/1.3419070 @Article{Petersen10, author = {M. K. Petersen and J. B. Lechman and S. J. Plimpton and G. S. Grest and in 't Veld, P. J. and P. R. Schunk}, title = {Mesoscale Hydrodynamics via Stochastic Rotation Dynamics: Comparison with {L}ennard-{J}ones Fluid}, journal = {J.~Chem.\ Phys.}, year = 2010, volume = 132, pages = 174106 } CITE-CITE-CITE-CITE-CITE-CITE-CITE-CITE-CITE-CITE-CITE-CITE-CITE Generated 0 of 1 mixed pair_coeff terms from geometric mixing rule SRD info: SRD/big particles = 17153 200 big particle diameter max/min = 1 1 SRD temperature & lamda = 1 0.063245553 SRD max distance & max velocity = 0.25298221 12.649111 SRD grid counts: 75 75 1 SRD grid size: request, actual (xyz) = 0.25, 0.24911072 0.24911072 1 SRD per actual grid cell = 5.544404 SRD viscosity = 0.23553122 big/SRD mass density ratio = 0.14250828 # of rescaled SRD velocities = 0 ave/max small velocity = 4.191188 7.6900178 ave/max big velocity = 2.6813242 7.1846103 Neighbor list info ... update: every = 1 steps, delay = 0 steps, check = yes max neighbors/atom: 2000, page size: 100000 master list distance cutoff = 2.8 ghost atom cutoff = 2.8 binsize = 18.683304, bins = 1 1 1 1 neighbor lists, perpetual/occasional/extra = 1 0 0 (1) pair lj/cut, perpetual attributes: half, newton on pair build: half/multi/atomonly/newton stencil: half/multi/2d bin: multi Per MPI rank memory allocation (min/avg/max) = 13.2 | 13.21 | 13.22 Mbytes Step Temp f_2[8] TotEng v_pebig v_ebig Press f_2[1] f_2[2] f_2[3] f_2[4] f_2[5] f_2[6] f_2[7] f_2[8] f_2[9] f_2[10] f_2[11] f_2[12] 0 6.8392143 0 0.297476 20.71529 25.810505 4.0555746 0 0 0 0 0 0 0 0 0 0 0 0 1000 1.2739082 3360 0.24704957 20.486195 21.435256 3.6693454 13497 46 46 2 816 28224 5625 3360 1.1564821 0 54 0 2000 1.3843858 3380 0.24759985 20.451634 21.483001 5.2299666 13363 70 70 0 1671 28224 5625 3380 1.170199 0 54 0 3000 1.3942166 3373 0.24823326 20.499268 21.537959 7.7943821 13214 59 59 2 2600 28224 5625 3373 1.1539593 0 54 0 4000 1.6387342 3366 0.24966206 20.441071 21.661928 4.3859226 13280 49 49 2 3568 28224 5625 3366 1.176006 0 54 0 5000 1.8677297 3388 0.25278915 20.541792 21.933251 5.9053775 13238 68 68 2 4553 28224 5625 3388 1.1728833 0 54 0 6000 1.8884914 3372 0.25216944 20.472555 21.879481 7.5864922 13142 62 62 1 5645 28224 5625 3372 1.1733967 0 54 0 7000 2.0575519 3387 0.25374609 20.483403 22.016279 6.9842803 13101 41 41 0 6805 28224 5625 3387 1.1503024 0 54 0 8000 1.9800593 3373 0.252975 20.474232 21.949376 8.3493951 13176 63 64 1 8166 28224 5625 3373 1.1621339 0 67 0 9000 2.2288114 3403 0.25526729 20.487802 22.148267 6.7676677 12866 61 61 1 9360 28224 5625 3403 1.1446891 0 67 0 10000 2.4854456 3339 0.25713924 20.45903 22.310687 9.3781009 12692 65 65 1 10680 28224 5625 3339 1.1417733 0 67 0 11000 2.5850677 3335 0.25820147 20.476975 22.402851 9.9421534 12954 70 70 2 11964 28224 5625 3335 1.1497985 0 67 0 12000 2.5087529 3358 0.25746572 20.469992 22.339013 9.9566718 12959 58 58 0 13462 28224 5625 3358 1.1365643 0 98 0 13000 2.5480838 3371 0.25761214 20.453395 22.351717 8.6628089 13142 54 54 3 14985 28224 5625 3371 1.1510123 0 98 0 14000 2.946645 3384 0.26176446 20.516743 22.711994 8.5668798 12579 53 53 0 16336 28224 5625 3384 1.1546089 0 98 0 15000 4.025292 3338 0.27188564 20.591315 23.590157 9.8722859 12824 50 50 15 18115 28224 5625 3338 1.164518 0 122 0 16000 2.2744945 3376 0.25598709 20.516221 22.21072 9.1890215 13020 52 52 0 19689 28224 5625 3376 1.1439385 0 122 0 17000 2.3857021 3353 0.25662954 20.489114 22.266462 10.24809 12776 51 51 0 21158 28224 5625 3353 1.1435041 0 122 0 18000 2.9678193 3330 0.26255063 20.56918 22.780206 8.6799225 12810 49 49 2 23066 28224 5625 3330 1.1567395 0 133 0 19000 2.7464034 3368 0.2613984 20.634162 22.680232 9.5420188 12746 47 47 3 24675 28224 5625 3368 1.1426658 0 133 0 20000 2.8228684 3367 0.26137363 20.575046 22.678083 8.0865322 12886 51 51 0 26119 28224 5625 3367 1.1484398 0 133 0 21000 2.8903033 3389 0.26173565 20.556218 22.709494 11.038294 13152 41 41 1 27685 28224 5625 3389 1.1398936 0 133 0 22000 2.8279828 3331 0.26058759 20.503035 22.609882 8.3647396 12895 57 57 1 29333 28224 5625 3331 1.1551348 0 133 0 23000 2.9320035 3376 0.26178899 20.529779 22.714121 7.1841698 13077 54 54 1 30908 28224 5625 3376 1.1453809 0 133 0 24000 2.8508425 3366 0.26104722 20.525884 22.649762 10.680819 13019 58 58 4 32831 28224 5625 3366 1.1391852 0 154 0 25000 2.7878254 3333 0.25961 20.448132 22.525062 11.149479 12960 57 57 1 34494 28224 5625 3333 1.172964 0 154 0 Loop time of 6.5335 on 4 procs for 25000 steps with 17353 atoms Performance: 330603.792 tau/day, 3826.433 timesteps/s, 66.400 Matom-step/s 99.3% CPU use with 4 MPI tasks x 1 OpenMP threads MPI task timing breakdown: Section | min time | avg time | max time |%varavg| %total --------------------------------------------------------------- Pair | 0.097519 | 0.10401 | 0.10744 | 1.2 | 1.59 Neigh | 0.027038 | 0.028067 | 0.028678 | 0.4 | 0.43 Comm | 0.39354 | 0.39697 | 0.40246 | 0.6 | 6.08 Output | 0.0013442 | 0.0014045 | 0.0015827 | 0.3 | 0.02 Modify | 5.8667 | 5.8905 | 5.9143 | 0.8 | 90.16 Other | | 0.1126 | | | 1.72 Nlocal: 4338.25 ave 4476 max 4199 min Histogram: 1 1 0 0 0 0 0 0 1 1 Nghost: 78.5 ave 83 max 75 min Histogram: 1 0 1 0 0 1 0 0 0 1 Neighs: 328 ave 352 max 309 min Histogram: 1 0 0 2 0 0 0 0 0 1 Total # of neighbors = 1312 Ave neighs/atom = 0.075606523 Neighbor list builds = 1274 Dangerous builds = 0 Total wall time: 0:00:06