Hongzhuo Yu / Northwestern Polytechnical University
Congshan Zhuo / Northwestern Polytechnical University
Chengwen Zhong / Northwestern Polytechnical University
Liu Sha / Northwestern Polytechnical University
The lattice Boltzmann method for multiphase flow simulations faces challenges such as excessive interfacial spurious velocities, numerical instability with large density ratios, and difficulty in capturing system equilibrium. In 2023, Ju [1] introduced the well-balanced (WB) model into the phase-field lattice Boltzmann framework, enabling accurate capture of the physical equilibrium state of two-phase fluid systems. This innovation reduces interfacial spurious velocities in stationary states to near machine error levels and achieves a divergence-free velocity field, thereby mitigating artificial compressibility effects and enhancing numerical stability. Building on this foundation, the present study conducts a comprehensive Chapman-Enskog (CE) expansion analysis and develops a regularized phase-field lattice Boltzmann model within the WB framework. The investigation focuses on equilibrium characteristics following phase interface changes under narrower interface thickness conditions and the model's capability to accurately simulate static contact angles. Current research demonstrates that the regularized model maintains high accuracy in both stationary and dynamic interface states, as well as static contact angle simulations, by suppressing higher-order moments. Furthermore, it exhibits improved numerical stability compared to conventional approaches. This work contributes to advancing the phase-field lattice Boltzmann method by addressing critical challenges and improving its reliability and performance in multiphase flow simulations.