How to set the heat conductivity and thermal diffusion coefficient in LB simulation?

Hi, everyone,
In thermal LB simulation, the thermal diffusion coefficient can determine the temperature field, but how to get or set the heat conductivity?
I am very confused about this.
Looking forward for your help.

How to set the interface condition:k[sub]s[/sub]dT[sub]1[/sub]=k[sub]f[/sub]dT[sub]2[/sub]?

Hi Nash,

For D2Q9 model, thermal diffusivity for diffusion problem can be set with the help of 
D=(1/3) x (tau-0.5) x (deltax)^2/ (deltat)
where, D= Diffusion coefficient
           tau= relaxation time
           deltax= distance between nodes
           deltat= time step