2018/12/06 by Chunhua Zhang, Zhaoli Guo, Zhang, Chunhua +3
Engineering · #76T10 #76Txx #FOS: Physical sciences #Fluid Dynamics (physics.flu-dyn) #Fluid Dynamics and Turbulent Flows #Heat and Mass Transfer in Porous Media #Lattice Boltzmann Simulation Studies
paper · pdf · doi:10.48550/arxiv.1812.02459
openalex publication_date 2018/12/06 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
In this paper, a fractional step lattice Boltzmann method is proposed to model two-phase flows with large density differences by solving Cahn-Hilliard phase-field equation and the incompressible Navier-Stokes equations.In order to maintain a hyperbolic tangent property of the interface profile and conserve the volume, an interfacial profile correction term and a flux correction term are added into the original Cahn-Hilliard equation respectively. By using a fractional step scheme, the modified Cahn-Hilliard equation is split into two sub-equations. One is solved in the framework of lattice Boltzmann equation method. The other is solved by the finite difference method. Compared with the previous lattice Boltzmann methods, the proposed method is able to maintain the order parameter within a physically meaningful range, which is conductive to track the interface accurately. In addition, the multi-relaxation-time collision model and a high-order compact selective filter operation are employed to enhance the numerical stability. The proposed method can simulate two-phase fluid flows with the density ratio up to 1000. In order to validate the accuracy and capability of the method, several benchmark problems, including single vortex deform of a circle, translation of a drop, Laplace-Young law, capillary wave and rising bubble with large density ratios, are presented. The results are in good agreement with the analytical solutions and the data in the literature for the investigated benchmarks.