In this paper, a phase-field-based multiple-relaxation-time lattice Boltzmann (LB) model is proposed for incompressible multiphase flow systems. model, one distribution function used to solve the Chan-Hilliard equation and other adopted Navier-Stokes equations. Unlike previous LB models, proper source term incorporated in interfacial evolution such that can be derived exactly also pressure designed recover correct hydrodynamic Furthermore, velocity fields calculated explicitly. A series of...

In this paper, we present a simple and accurate lattice Boltzmann (LB) model for immiscible two-phase flows, which is able to deal with large density contrasts. This utilizes two LB equations, one of used solve the conservative Allen-Cahn equation, other adopted incompressible Navier-Stokes equations. A forcing distribution function elaborately designed in equation make it much simpler than existing models. addition, proposed can achieve superior numerical accuracy compared previous type...

In this paper, based on multicomponent phase-field theory we intend to develop an efficient lattice Boltzmann (LB) model for simulating three-phase incompressible flows. model, two LB equations are used capture the interfaces among three different fluids, and another equation is adopted solve flow field, where a new distribution function forcing term delicately designed. Different from previous multiphase models, interfacial force not in computation of fluid velocity, which more reasonable...

In this paper, a comparative study of the lattice Boltzmann (LB) models for Allen-Cahn (A-C) and Cahn-Hilliard (C-H) equations is conducted. To end, new LB model A-C equation first proposed, where equilibrium distribution function source term are delicately designed to recover correctly. The gradient in can be computed by nonequilibrium part such that collision process implemented locally. Then detailed numerical on several classical problems performed give comparison between present...

Within the phase-field framework, we present an accurate and robust lattice Boltzmann (LB) method for simulating contact-line motion of immiscible binary fluids on solid substrate. The most striking advantage this lies in that it enables us to handle two-phase flows with mass conservation a high density contrast 1000, which is often unavailable existing multiphase LB models. To simulate fluid flows, utilizes two evolution equations, are respectively used solve conservative Allen-Cahn...

In this paper, a lattice Boltzmann (LB) model with double distribution functions is proposed for two-phase flow in porous media where one function used pressure governed by the Poisson equation and other applied saturation evolution described convection-diffusion source term. We first performed Chapman--Enskog analysis show that macroscopic nonlinear equations can be recovered correctly from present LB model. Then framework of method, we adopted local scheme developed some previous works...

Modeling thermal multiphase flows has become a widely sought methodology due to its scientific relevance and broad industrial applications. Much progress been achieved using different approaches, the lattice Boltzmann method is one of most popular methods for modeling liquid–vapor phase change. In this paper, we present novel model accurately simulating The proposed built based on equivalent variant temperature governing equation derived from entropy balance law, in which heat capacitance...

In this paper, the three-dimensional (3D) Rayleigh-Taylor instability (RTI) with low Atwood number (${A}_{t}=0.15$) in a long square duct ($12W\ifmmode\times\else\texttimes\fi{}W\ifmmode\times\else\texttimes\fi{}W$) is studied by using multiple-relaxation-time lattice Boltzmann (LB) multiphase model. The effect of Reynolds on interfacial dynamics and bubble spike amplitudes at late time investigated detail. numerical results show that sufficiently large numbers, sequence stages 3D immiscible...

In this paper, a phase-field-based lattice Boltzmann (LB) model is proposed for axisymmetric multiphase flows. Modified equilibrium distribution functions and some source terms are properly added into the evolution equations such that flows in coordinate system can be described. Different from previous LB models, arise effect contain no additional gradients, therefore present much simpler. Furthermore, through Chapmann-Enskog analysis, Chan-Hilliard equation Navier-Stokes exactly derived...

In this paper, we present a numerical study on the deformation and breakup behavior of liquid droplet past solid circular cylinder by using an improved interparticle-potential lattice Boltzmann method. The effects eccentric ratio $\ensuremath{\beta}$, viscosity $\ensuremath{\lambda}$ between surrounding fluid, surface wettability, Bond number (Bo) dynamic are considered. parameter $\ensuremath{\beta}$ represents degree that deviates from center line, Bo is inertial force capillary force....

In this paper, we conduct the high-resolution direct numerical simulations of multimode immiscible Rayleigh-Taylor instability (RTI) with a low Atwood number (At = 0.1) using an improved phase field lattice Boltzmann method. The effect Reynolds on evolutional interfacial dynamics and bubble/spike amplitudes is first investigated by considering its wide range, from 100 up to high value 30 000. results show that, for sufficiently large numbers, sequence distinguishing stages in RTI can be...

Based on the phase-field theory, we present an improved lattice Boltzmann (LB) method for simulating droplet dynamics with soluble surfactants. This takes advantage of three sets particle distribution functions solving coupled system two Cahn–Hilliard-like equations and incompressible Navier–Stokes equations. The model is formulated from perspective Ginzburg–Landau free energy functional, where some modifications introduced circumvent unphysical behavior interfacial layer improve...

In this paper, the late-time description of immiscible Rayleigh–Taylor instability (RTI) in a long duct is numerically investigated over comprehensive range Reynolds numbers (1≤Re≤10 000) and Atwood (0.05≤A≤0.7) using mesoscopic lattice Boltzmann method on high-resolution meshes. It found that with high number undergoes sequence distinguishing stages, which are termed as linear growth, saturated velocity reacceleration chaotic development stages. The dynamics spike bubble from growth stage...

In this work, a phase-field-based lattice Boltzmann method with reduced spurious velocity is developed for axisymmetric incompressible two-phase flows. Two sets of equations multiple-relaxation-time collision operators are used to, respectively, recover the conservative Allen–Cahn equation interface capturing and hydrodynamic equations. To reduce velocity, novel correction term introduced into so that leading truncation error related to third derivatives pressure can be partially removed....

Small-scale microscopic phenomena determine the behavior of large-scale droplets, which brings great challenges to accurately simulate droplet coalescence process. In this paper, mesoscopic lattice Boltzmann method based on phase field theory is used collision and binary three-dimensional droplets in a confined shear flow. The numerical prediction was first compared with experimental result, good agreement reported. Then, we investigated influences comprehensive range capillary numbers...