diffusion coefficient..

Hi palabos community,

I have seen some diffusivity equations with a strange dt term in several papers. I am wondering what means “dt” when they put it inside the equation of the diffusivity, such as:

Diff = dt * (tau - 0.5) *c**2 / 3 or Diff = dt * c_s * (tau - 0.5)

where c =dx/dt
dx = dt = 1/Ly
tau = relaxation time for diff scalar.

Ly is the number of nodes that conform the characteristic lenght of the model.

where does the “dt” come from?

Does it have something to do with some LB units? Can it be minimally explianed?

Thanks in advanced,


Lets ignore it!

From the chapman enskog analysis …