Numerical benchmarking of fluid–structure interaction: An isogeometric finite element approach

•Describes an isogeometric finite element code for fluid–structure interaction.•Simulates benchmark problem at Re=100 for cylinder with attached flexible bar.•Investigates the use of linear, quadratic and cubic spline elements.•Sensitivity to mesh resolution and mesh stiffness distribution is investigated.•Quadratic and cubic spline elements estimate lift, drag and displacements well.

In this paper we describe and evaluate an isogeometric finite element program, IFEM-FSI, for doing coupled fluid–structure interaction simulations. We investigate the role played by employing higher polynomial orders and higher regularity for solving a well known benchmark problem for flow past a circular cylinder with an attached flexible bar at Reynolds number Re=100. Furthermore, we investigate the sensitivity to resolution in the fluid mesh as well as stiffness distribution in the mesh movement algorithm. Mesh quality is also assessed. Our simulations indicate that quadratic and cubic spline elements give better estimation of lift, drag and displacements than linear spline elements.