A generalized lattice Boltzmann model for fluid flow system and its application in two-phase flows. (15th March 2020)

• Record Type: Journal Article
• Authors: Yuan, Xiaolei; Chai, Zhenhua; Wang, Huili; Shi, Baochang
• Is Part Of: Computers & mathematics with applications. Volume 79:issue 6(2020)
• Page Start: 1759
• Page End: 1780
• Publication Date: 2020-03-15
• Subjects: Generalized lattice Boltzmann model -- Source term -- Incompressible and nearly incompressible N–S equations -- Fluid flow system -- Two-phase flow; Electronic data processing -- Periodicals; Mathematics -- Data processing -- Periodicals; 510.28541
• DOI: 10.1016/j.camwa.2019.10.007
• Languages: English
• ISSNs: 0898-1221

Abstract

Abstract: In this paper, a generalized lattice Boltzmann (LB) model with a source term in the continuity equation is proposed to solve both incompressible and nearly incompressible Navier–Stokes (N–S) equations. This model can be used to deal with single-phase and two-phase flows problems with a source term in the continuity equation. From this generalized model, we can not only get some existing models, but also derive new models. Moreover, for the incompressible model derived, a modified pressure scheme is introduced to calculate the pressure, and then to ensure the accuracy of the model. In this work, we will focus on a two-phase flow system, and in the frame work of our generalized LB model, a new phase-field-based LB model is developed for incompressible and quasi-incompressible two-phase flows. A series of numerical simulations of some classic physical problems, including a spinodal decomposition, a static droplet, a layered Poiseuille flow, and a bubble rising flow under buoyancy, are performed to validate the developed model. Besides, some comparisons with previous quasi-incompressible and incompressible LB models are also carried out, and the results show that the present model is accurate in the study of two-phase flows. Finally, we also conduct a comparison between quasi-incompressible and incompressible LB models for two-phase flow problems, and find that in some cases, the proposed quasi-incompressible LB model performs better than incompressible LB models.