An efficient thermal lattice Boltzmann method for simulating three-dimensional liquid-vapor phase change

TL;DR

This paper introduces an efficient 3D thermal lattice Boltzmann method for simulating liquid-vapor phase change, avoiding complex gradient calculations and utilizing a simplified velocity model for improved performance.

Contribution

The paper develops a novel 3D thermal LB model based on the D3Q7 lattice that is more efficient and easier to implement, without needing to compute volumetric heat capacity gradients.

Findings

Numerical results agree well with analytical solutions and experimental data.

The method effectively simulates temperature distribution and droplet evaporation.

The approach is reliable and computationally efficient for 3D phase change simulations.

Abstract

In this paper, a multiple-relaxation-time lattice Boltzmann (LB) approach is developed for the simulation of three-dimensional (3D) liquid-vapor phase change based on the pseudopotential model. In contrast to some existing 3D thermal LB models for liquid-vapor phase change, the present approach has two advantages: for one thing, the current approach does not require calculating the gradient of volumetric heat capacity [i.e., $\nabla \left( {\rho {c_v}} \right)$], and for another, the current approach is constructed based on the seven discrete velocities in three dimensions (D3Q7), making the current thermal LB model more efficient and easy to implement. Also, based on the scheme proposed by Zhou and He [Phys Fluids 9:1591-1598, 1997], a pressure boundary condition for the D3Q19 lattice is proposed to model the multiphase flow in open systems. The current method is then validated by considering the temperature distribution in a 3D saturated liquid-vapor system, the $d^2$ law and the droplet evaporation on a heated surface. It is observed that the numerical results fit well with the analytical solutions, the results of the finite difference method and the experimental data. Our numerical results indicate that the present approach is reliable and efficient in dealing with the 3D liquid-vapor phase change.