A novel scheme for curved moving boundaries in the lattice Boltzmann method

摘要

We propose a novel scheme to handle moving boundaries, both straight and curved, within the lattice Boltzmann method (LBM). In this scheme, which is broadly based on the Chapman-Enskog expansion, the fictitious distributions are constructed exactly on the moving boundary. This is in contrast to existing methods where such distributions are constructed on neighboring nodes which may not lie on the moving boundary. The post-collisional distributions on the fluid nodes near the moving boundary are then constructed using first-or second-order interpolations. The proposed scheme also overcomes the requirement to have separate interpolation formulations for different values of the intersection parameter. Several validation tests presented here indicate improved accuracy and numerical stability, compliance with Galilean invariance principle, an ability to preserve the geometric fidelity of curved surfaces.