The Appropriate Blend Proportional Factor Value of Two Staggered Grids Used in the Free Energy Based LBM With Large Density Ratio

The effect of blend proportional factor α used in the free energy based two-phase flow LBM model with large density ratio on the shape description of a water droplet is investigated. The blend proportional factor α which combines the two kinds of staggered grids is adopted in the calculation process of the Poisson equation based fractional step method to satisfy the mass conservation in the LBM scheme, it is found to lead to varied degrees of shape deformation of a simulated liquid water droplet. The shape deformation degree of a liquid water droplet with certain dimensionless radius is measured by the radius lengths in 8 directions. The appropriate α which gives the better shape description accuracy of a water droplet with certain dimensionless radius is explored and its value change tendency with the dimensionless radius lengths is summarized. The α’s effect on the shape deformation is also presented.