The query arises different points of the model I am trying to explore which I am going to explain step wise as followed:

(i) I am trying to simulate a two-phase immiscible flow in a porous media for which I am using multicomponent Shan Chen Lattice Boltzmann method.

(ii) As followed through the works of Dr. Haibo Huang and Dr. Sukop, I have considered major and minor densities in such a way that Gc*(rho)>1 to keep immiscibility. Doing the benchmarks with these example really helped me out but with porous media it started to make some trouble i.e. it seemed that the two components are miscible.

(iii) The boundary conditions used are (i) inlet: constant velocity inlet BC (ii) outlet: extrpolation boundary condition

My queries are:

(i) Is it something I am making a mistake in the model or should I see alternatives e.g. color gradient LBM which is popular for immiscible fluid displacement?