Dear All,

I’m trying to calculate the thermal conductivity of a multi component system, a nanofluid.

Since, the heat/flux compute in lammps only calculates thermal conductivity for a single component system. I was wondering if anyone has made changes to the heat/flux compute or made a new compute to enable multi component system calculation and if you are willing to share that with me.

Your help would be much appreciated. Thank you.

Best regards,

Yunes Salman

The compute heat/flux is not limited to single component systems. The example script included in the manual refers to a single component system (solid Ar).

There is no need to modify the existing code or add a new compute for multicomponent systems.

Best regards

Evangelos Voyiatzis

Στις Τετ 9 Μαρ 2022 στις 2:05 μ.μ., ο/η Salman, Yunes <[email protected]> έγραψε:

Dear Evangelos,

Thank you for your reply.

Do you know what I need to change in the provided example to make it work for a multicomponent system?

Best regards,

Yunes Salman

The lines (taken from the example file https://docs.lammps.org/compute_heat_flux.html)

```
reset_timestep 0
compute myKE all ke/atom
compute myPE all pe/atom
compute myStress all stress/atom NULL virial
compute flux all heat/flux myKE myPE myStress
variable Jx equal c_flux[1]/vol
variable Jy equal c_flux[2]/vol
variable Jz equal c_flux[3]/vol
fix JJ all ave/correlate $s $p $d &
c_flux[1] c_flux[2] c_flux[3] type auto file J0Jt.dat ave running
variable scale equal ${convert}/${kB}/$T/$T/$V*$s*${dt}
variable k11 equal trap(f_JJ[3])*${scale}
variable k22 equal trap(f_JJ[4])*${scale}
variable k33 equal trap(f_JJ[5])*${scale}
thermo_style custom step temp v_Jx v_Jy v_Jz v_k11 v_k22 v_k33
run 100000
variable k equal (v_k11+v_k22+v_k33)/3.0
variable ndens equal count(all)/vol
print "average conductivity: $k[W/mK] @ $T K, ${ndens} /A\^3"
```

```
are applicable to both single component and multicomponent systems. They compute the thermal conductivity of the whole system. You don't need to change anything.
```

```
Best regards
Evangelos
```

Στις Δευ 14 Μαρ 2022 στις 11:31 μ.μ., ο/η Salman, Yunes <[email protected]> έγραψε: