# Some Question

Dear all,
We are a grouo of students,we tried to implement a 2D channel multhiphase flow, we based on the matlab examples.After we stopped, there were two problems:

1. Once you have chosen to simulate liquids, which are the values attributed to the constant G (amplitude of the iteraction Strength) in ShanChen.m ?

2. regarding the initialization of the two fluids, we have:
fIn = reshape( tNS’ * zeros(1,lxly), 9, lx, ly);
gIn = reshape( tNS’ * ones(1,lx
ly), 9, lx, ly);
So Hypothesis is that the channel is filled with a fluid and the other is vacuum , but numerical simulations does uncorrect results.
how can we initialize these two fluids?

anyone have any ideas to solve these two questions?

Thanks for help

Hi Gabrielle,

You need to initialize it from the equation of state density values. It’s not vacuum - if you put 0 density you will have the simulation blown up. You can find all these curves in original papers of Shan-Chen or Succi-Sbragaglia. One of the examples what I use is G=-6 and rhog=0.1 and rhol=1.8.

You can find more in my thesis http://www.lbmethod.org/_media/hosted_doc:kuzmin-thesis.pdf to take values.

Hopefully it will help,
Alex