A Lattice Boltzmann approach for immiscible fluids with very different viscosities

摘要

In this article, a lattice Boltzmann model for two immiscible fluids with same density but a large viscosity difference is developed. The effect of surface tension is included. An indicator function is used to model the interface motion and is updated by a lattice Boltzmann scheme. The macroscopic equation for this function is derived using multiscale analysis. Numerical results are compared with theoretical and experimental ones for the problem of drop deformation under steady linear flows. A qualitative comparison with results given by a level contour reconstruction method for drop collision in three dimensions is also shown. Other numerical applications, such as flow past obstacles and a falling drop, are presented.