Grid independence test for mixed convection problem

Lattice Boltzmann Method LBM: Theory
#1

Hi Friends,

I am trying to simulate mixed convection problem using Lattice Boltzmann method, and trying to make it grid independent.
I have assigned the values in the following way:
grid size: nx=200, ny=200
alpha=0.0141
visco=0.01
Prandtl number=0.71
tauf=(3visco+0.5)…for momentum distribution function
taug=(3alpha+0.5)…for thermal distribution function
u_top=(Re*visco)/(sqrt(3)nx)
Ma=u_top(sqrt(3))
Now, this top lid velocity(u_top) is used in the iterations to calculate the macroscopic variables. Since, u_top is depending on grid size, so every time this input parameter gets changed with changing grid size.Hence, I am facing problem with this grid independence test. It would be a great help if anyone can suggest me any solution.

Shikha

#2

Hi
if you use the incompflowparam class in palabos, you should check how it calculates the parameters. In LB parameters are related to each other so you cannot set all the parameter independently. To be sure as output parameters, you can print all initial parameter you set and see if the palabos change any of them?

Regards