Hi I am trying to simulate water vapour condensating into liquid droplets.

I found a sample Matlab script on this site which claims to use the Shan Chen model:

Phys. Rev. E 47, 1815 - 1819 (1993)

Lattice Boltzmann model for simulating flows with multiple phases and components

[prola.aps.org/abstract/PRE/v47/i3/p1815_1]

Having looked through the sample I fail to see how it actually utillises the method described in this paper. It successfully simulates mixing in a mixture of two fluids clearly exhibiting surface tension. It does however not deal with phase transition. The easiest way of identifying this is by realising that the distrubution function for the subsequent timestep fully depends on rho. Meaning that if a phase doesn’t exist it never will. However phase transition as described in the paper mentioned occurs even with zero rho.

More on the point I am having some troubles successfully implementing the theory in this paper. How does one go about determining all the constants in the equilibrium function:

d_0, D, b and c. I can find u and e_a obviously and I have a suspicion c would be sqrt(3RT) but for the others I do not know.

Hopefully somebody could shed some light on my problem.

Regards,

Aleks