A novel fluid-structure interaction algorithm for compressible flows and deformable structures

In this study, we propose a new immersed boundary method for compressible fluid-structure interaction simulations. We take a partitioned coupling strategy that comprises three parts: fluid solver, structure solver, and fluid-structure boundary treatment. The fluid solver is implemented by a second-order finite volume scheme, and the structure is solved by an implicit finite element solver. For the boundary treatment, this method employs a multilevel marking algorithm to determine the direction from the inside of the structure to the outside. Following the direction, fluids that permeate the structure are transported out of the structure boundaries to satisfy the boundary conditions. This method strictly maintains mass conservation and uses no cross-boundary fitting or interpolation; thus, it appears to be convenient when treating complex-shaped or deformable structures and diminishes the singularity problem. The 1D and 2D numerical experiments show that our method is capable of obtaining approximately first-order convergent results, agreeing well with the published data. The method's limitations are discussed in the conclusion.