LBM for Complex Multiphase Dynamics: Interfacial Physics, Models, and Applications

The Lattice Boltzmann Method (LBM) is a mesoscopic computational fluid dynamics (CFD) technique that has emerged as a powerful and flexible approach for simulating multiphase and multicomponent flows. Unlike conventional Navier-Stokes-based methods, which solve the macroscopic conservation equations, LBM operates at the kinetic level by modeling the evolution of particle distribution functions on a discrete lattice. This kinetic foundation allows LBM to naturally capture interfacial dynamics, phase separation, and complex fluid-fluid interactions without the need for explicit interface tracking algorithms such as VOF or Level-Set methods.The primary appeal of LBM for multiphase problems lies in its intrinsic ability to model interfacial phenomena through local particle interactions. By incorporating interparticle forces or free-energy functionals directly into the collision step, LBM can simulate phase segregation, surface tension, wetting effects, and droplet or bubble formation as emergent phenomena. This makes it particularly effective for flows with complex geometries, moving interfaces, or multiple fluid components, including porous media, microfluidics, boiling and condensation, and emulsion processing.Key strengths of LBM include its simple handling of complex boundaries, excellent parallel scalability, and ability to couple with additional physics such as heat transfer, chemical reactions, and external fields. However, challenges remain in simulating high-density and high-viscosity ratios as well as high-Reynolds-number flows with sufficient numerical stability. Popular multiphase LBM models include the Shan-Chen (pseudopotential) model, the color-gradient model, and the free-energy-based model, each offering different trade-offs between computational efficiency, physical accuracy, and numerical stability.LBM continues to be a vibrant research area in computational physics and engineering, bridging the gap between microscopic interactions and macroscopic multiphase flow behavior, with broad applications in energy systems, biomedical devices, material processing, and environmental engineering.This Research Topic welcomes contributions across the following research themes within multiphase flow LBM:• High-density and high-viscosity ratio models• Thermodynamic consistency and phase change models• Compressible multiphase flow models• Non-Newtonian multiphase flow models• High-performance computing and algorithm optimization• Microscale and nanoscale multiphase flow• Multiphase flow in porous media• Phase change heat transfer, including boiling and condensation• Interface instability and complex structural evolution• Particle, bubble, and droplet-fluid multiphase systems• Fluid-solid coupling and biological flow• Electric and magnetic fluid dynamics in multiphase flow• Chemical reaction multiphase flow• Data-driven and machine learning-enhanced LBM Topic editors: Lei Wang, Ankang Gao, Linlin Kang Source: https://www.frontiersin.org/research-topics/76960/lbm-for-complex-multiphase-dynamics-interfacial-physics-models-and-applications