Reply To: Multicomponent flow- water droplet splashing
In most cases you can use the converter provided by OpenLB to convert from non-dimensional to dimensional numbers.
Do note that the pressure in the converter assumes no pseudopotential modification, i.e.:
p = cs^2 * ρ and not
p = cs^2 *( ρ + G/2 Ψ^2 )
I can highly recommend the book The Lattice Boltzmann Method Principles and Practice by Krüger et al.
They have a good section on multicomponent flow. They also detail how to convert from dimensional to non-dimensional numbers.
Even when simulating a droplet at rest, there are always spurious currents that arise. Those are numerical artifacts and aphysical, however that means that there is a non-zero velocity component in the simulation. You also have the grid spacing dx and time step dt to work with.
The surface tension that emerges in LBM is a function of the pseudopotential and not density as it is in real life. Thus your surface tension depends on your pseudopotential function used.
Since I have purely worked with single component multiphase flow, I cannot help you with your rayleighTaylor2d omega problem.