# sample LAMMPS input script for thermal conductivity of liquid LJ # use fix ehex to add/subtract energy from 2 regions # settings variable x equal 10 variable y equal 10 variable z equal 20 variable rho equal 0.6 variable t equal 1.35 variable rc equal 2.5 #variable rho equal 0.85 #variable t equal 0.7 #variable rc equal 3.0 # setup problem units lj atom_style atomic lattice fcc ${rho} region box block 0 $x 0 $y 0 $z create_box 1 box create_atoms 1 box mass 1 1.0 velocity all create $t 87287 pair_style lj/cut ${rc} pair_coeff 1 1 1.0 1.0 neighbor 0.3 bin neigh_modify delay 0 every 1 # heat layers region hot block INF INF INF INF 0 1 region cold block INF INF INF INF 10 11 compute Thot all temp/region hot compute Tcold all temp/region cold # 1st equilibration run fix 1 all nvt temp $t $t 0.5 thermo 100 run 1000 velocity all scale $t unfix 1 # 2nd equilibration run fix 1 all nve fix hot all ehex 1 100.0 region hot fix cold all ehex 1 -100.0 region cold thermo_style custom step temp c_Thot c_Tcold thermo 1000 run 10000 # thermal conductivity calculation compute ke all ke/atom variable temp atom c_ke/1.5 compute layers all chunk/atom bin/1d z lower 0.05 units reduced fix 2 all ave/chunk 10 100 1000 layers v_temp file profile.ehex variable tdiff equal f_2[11][3]-f_2[1][3] fix ave all ave/time 1 1 1000 v_tdiff ave running start 13000 thermo_style custom step temp c_Thot c_Tcold v_tdiff f_ave run 20000