Coupled material point Lattice Boltzmann method for modeling fluid–structure interactions with large deformations

Abstract

Fluid–structure interactions (FSI) are very common in many natural processes and engineering applications. However, modeling FSI with large structural deformations and turbulence flows under high Reynolds number (Re) is still a challenging task. Here, we present a hybrid 3D model that combines the advantages of Lattice Boltzmann Method (LBM) in solving complex flow problems and the capability of Material Point Method (MPM) in handling large structural deformations. A sharp interface coupling scheme is presented in detail and a LES sub-grid model is adapted for turbulent flows. The structure solver is validated by comparing with Euler beam theory and the fluid solver is tested for fluid round circle and cube obstacles under a large range of Re. The coupled model is validated by simulations of a flexible plate deformation in shear flows. Good agreements are found comparing with experimental results. Finally some applications of importing realistic geometries from Computer Assisted Design (CAD) software, are shown to demonstrate the future applications of the method.