We propose a multiple relaxation time entropic realization of a recent twophase flow lattice Boltzmann model[S.A.Hosseini,B.Dorschner,and I.V.Karlin,Journal of Fluid Mechanics 953(2022)].While the original model with ...We propose a multiple relaxation time entropic realization of a recent twophase flow lattice Boltzmann model[S.A.Hosseini,B.Dorschner,and I.V.Karlin,Journal of Fluid Mechanics 953(2022)].While the original model with a single relaxation time allows us to reach large density ratios,it is limited in terms of stability with respect to non-dimensional viscosity and velocity.Herewe showthat the entropic multiple relaxation time model extends the stability limits of the model significantly,which allows us to reach larger Reynolds numbers for a given grid resolution.The thermodynamic properties of the solver,using the Peng-Robinson equation of state,are studied first using simple configurations.Co-existence densities and temperature scaling of both the interface thickness and the surface tension are shown to agree well with theory.The model is then used to simulate the impact of a drop onto a thin liquid film with density and viscosity ratios matching those of water and air both in two and three dimensions.The results are in very good agreement with theoretically predicted scaling laws and experimental data.展开更多
基金supported by European Research Council(ERC)Advanced Grant no.834763-PonD(S.A.H,B.D.and I.K.)the Swiss National Science Foundation(SNSF)grant No.200021-172640(S.A.H.)。
文摘We propose a multiple relaxation time entropic realization of a recent twophase flow lattice Boltzmann model[S.A.Hosseini,B.Dorschner,and I.V.Karlin,Journal of Fluid Mechanics 953(2022)].While the original model with a single relaxation time allows us to reach large density ratios,it is limited in terms of stability with respect to non-dimensional viscosity and velocity.Herewe showthat the entropic multiple relaxation time model extends the stability limits of the model significantly,which allows us to reach larger Reynolds numbers for a given grid resolution.The thermodynamic properties of the solver,using the Peng-Robinson equation of state,are studied first using simple configurations.Co-existence densities and temperature scaling of both the interface thickness and the surface tension are shown to agree well with theory.The model is then used to simulate the impact of a drop onto a thin liquid film with density and viscosity ratios matching those of water and air both in two and three dimensions.The results are in very good agreement with theoretically predicted scaling laws and experimental data.