COUPLING MOLECULAR DYNAMICS AND PSEUDOPOTENTIAL LATTICE BOLTZMANN METHOD WITH NONIDEAL EQUATION OF STATE FOR MICROSCOPIC FLUID FLOWS

A coupled numerical model between the molecular dynamics (MD) and the pseudopotential lattice Boltzmann method (LBM) is proposed in this work. By using the equation of state (EOS) corresponding to the MD simulation, the pseudopotential LBM can reproduce the same phase separation phenomenon as the MD. The coupling schemes are validated and the coupling method is tested by the simulation of flow past a carbon nanotube. The MD is used near the nanotube and the LBM is employed in the surrounding region. The results show that the compressible effect of the fluid can be captured by the coupling method, and better continuities of the density and velocity across the interfaces are obtained. In addition, the behavior of a nanodroplet on a surface is simulated by the coupling model. The MD is used near the surface to consider the effect of wettability. The transportation of the two phases through the coupling interface is achieved. The proposed model has the potential to be used in the simulations of microscopic multiphase problems.