Simulation of Flows and Acoustic Field Around Moving Body by ALE Formulation in Finite Difference Lattice Boltzmann Method

Abstract

The flow-field and the acoustic-field around moving bodies are simulated by the Arbitrary Lagrangian Eulerian formulation in the finite difference lattice Boltzmann method. The validity of the ALE is checked by comparing flow about a square cylinder in ALE formulation and that in the fixed coordinates, and both agree very well. Matching procedure between the moving grid and fixed grid is also considered. The proposed method in which the both grids are connected through buffer region is shown to be superior to moving overlapped grid. Dipole-like emissions of sound wave from harmonically vibrating bodies in two- and three-dimensional cases are simulated. Sound wave emitted from rapidly rotating elliptic cylinder is also successfully simulated.