A fully-coupled three-dimensional fluid-structure interaction study on the externally-pressurized collapsible tube and the internal flow

We study the behavior of a collapsible tube conveying a fluid subject to external pressure that could occur in many physiological applications. The method of rotating spines is developed to enable an automatic mesh adaptation when the tube is deformed largely. We examine bifurcation diagrams when the tube is collapsed under a pressure driven condition and reveal that multiple solutions exist for a range of the Reynolds number. The stability characteristic of the system is discovered by determining stability of these solutions by the eigenvalue method for the first time, which is validated by solving a time-dependent problem of the system.