A Geometry-Adaptive Immersed Boundary-Lattice Boltzmann Method for Modelling Fluid-Structure Interaction Problems

The immersed boundary method has been extensively used in many areas. However, there are two typical challenges for modelling fluid-structure problems at moderate and high Reynolds numbers (e.g. 10(3) -10(5)). One is the size of mesh at high Reynolds numbers when the standard immersed boundary method is applied. The other is the numerical instability associated with the partitioned coupling for fluid-structure interaction problems involving small structure-to-fluid mass ratios. To address the challenges, a novel computational framework which combines the lattice Boltzmann method and an improved immersed boundary method based on a dynamic geometry-adaptive Cartesian grid is presented. A few classic validations are conducted to demonstrate the accuracy of the current method.