Study On Surface Tension Model And Algorithm For Two-phase Flows

Two-phase flows is widely used in nature and industry,so it is of great significance to study two-phase flow.Because surface tension plays an important role in fluid flow and interface movement,accurate modeling of surface tension is the key to numerical simulation of two-phase flow.Therefore,it is of great significance to study the surface tension model with good properties and efficient numerical algorithm based on the phase field method.This paper uses the relationship between the Level Set function and the phase field function to calculate the surface tension based on the continue surface tension model of the Level Set function,and proposes a continuum surface tension model based on the phase field method.This model not only has the advantages of solving multiphase flow problems with phase field model,but also inherits the advantages of continuum surface tension model based on Level Set function.Furthermore,on the surface tension model,combined with the multiphase lattice Boltzmann flux solver(MLBFS),the mathematical model of two-phase fluid problem is given,and an efficient,stable and conservative numerical algorithm is proposed.Finally,the examples of Laplace Law,droplet merging and droplet deformation in shear flow are successfully simulated,which verifies that the proposed model and algorithm have good stability and conservation.