in the multicomponent2D example, the initial setup is that the densities of the two fluids are close to 1 with small perturbation. However, when I change the density of one fluid to 0.5, (the other one is around 1), then, during simulation, the fluid with larger density tends to expand dramatically, resulting in the densities of both two fluids being around 0.8.
Why does this happen? shouldn’t the fluids be incompressible in LBM?
How do I modify the codes to achieve different densities of fluids?
Thank you very much,