[lammps-users] fix thermal/conductivity ; about heat fulx

Dear all,

We know thermal conductivity=-heat flux/temperature profile;

This is what I written in my input file:

………

fix fluxLi Li_ions thermal/conductivity 10 z 24 swap 1

fix fluxF F_ions thermal/conductivity 10 z 24 swap 1

compute ke all ke/atom

variable temp atom c_ke[]/0.0001292355

fix 4 all ave/spatial 1 50000 50000 z 0.0 2 v_temp file tmp.profile units box

thermo_style custom step temp press vol ke f_fluxLi f_fluxF

The output is like:

Step Temp KinEng fluxLi fluxF

150001 302.71508 39.089866 614.97774 589.9992

Therefore I think I should do something like:

Thermal conductivity =-1/2 (hear flux Li+heat flux F)/temperature profile

The factor 2 is because the hot layer is in the centre, and two cold layers are at the ends. As a result, the heat flux can go both way.

I don’t know what I thought is correct or not since in the lammps manual does specify this problem.

Anyone has any thoughts?

Best regards

Haiming

Please read the original Muller-Plathe paper on this -
it discusses the factor of 2.

Steve