[lammps-users] Are there errs in my codes of computing thermal conductivity of Argon?

The following is my codes about computing thermal conductivity of Argon, and the result is in the file attached. I find the result is higher than 0.132 which is in other author’s article and my result is also not very plat. And I find when I raise the number of particles , the result will be even bad, and this is obviously wrong. Please check whether it’s right or not for me, thanks

# MD simulation of Ar thermal conductivity
# Initialization
units lj
dimension 3
newton on
boundary p p p
atom_style dpd
neighbor 0.3 bin
neigh_modify check yes
lattice fcc 0.844
region box block 0 3 0 3 0 3 units lattice
create_box 1 box
create_atoms 1 box
mass 1 1.0
velocity all create 0.71 4928459 rot yes dist gaussian units box
pair_style lj/cut 2.8
pair_modify tail no
pair_coeff 1 1 1.0 1.0 2.8 # LJ parameters for Ar-Ar
fix nvt all nvt 0.71 0.71 0.2
thermo_style custom step temp etotal vol
thermo_modify lost warn
thermo 10
# Run
timestep 0.002
run 100000
reset_timestep 0
compute myPE all pe/atom pair
compute flux all heat/flux myPE
log flux.log
variable J1 equal c_flux[1]/vol
variable J2 equal c_flux[2]/vol
variable J3 equal c_flux[3]/vol
thermo_style custom step temp v_J1 v_J2 v_J3
restart 100000 restart.*
run 900000


TC_Ar.wmf (9.09 KB)