Numerical simulation for interaction between 3D thin-walled structure and fluid

Using a computational fluid dynamics (CFD) solver and the 3D nonlinear shell finite element code developed by the authors, a numerical method for the interactions between 3D thin-walled structure and fluid was proposed. The viscous flow was solved using the CFD solver, Fluent, while the large deformation of thin-walled structure was solved by the 3D nonlinear shell-based finite element code. The staggered method was used to couple the fluid and the structure. First, a benchmark problem was used to verify the reliability of the finite element code in solving buckling and post-buckling behaviors of thin-walled structures. Second, a problem with a collapsible tube conveying viscous fluid was simulated. The good agreement between the results obtained by the present method and those published in literatures shows the reliability of the present method in dealing with the interactions of thin-walled structure and viscous fluid. Finally, the interaction of fluid and structure in forced expiration was investigated. The emphasis of the project was laid on the effect between collapsible tube and viscous flow in bifurcating airways.