Numerical Simulation of Tube Bundle Vibrations Under Cross Flow

The present paper is dealing with the simulation of instability for a moving tube in a fixed tube bundle. The purpose is to improve the understanding of the instability threshold phenomenon by means of comparisons between numerical, experimental and analytical solutions. An improved serial staggered procedure is used for the coupling between the fluid and the structure solvers and an Arbitrary Lagrange-Euler (ALE) method is introduced to solve the flow in the presence of moving structures. Two flow solvers are compared, one with finite volume and one with finite element method. The moving tube is assumed rigid. First, the added mass and damping coefficients of the moving tube are computed in quiescent fluid and they are compared to an analytical solution. Second, the vibrations of the tube in a tube bundle under laminar cross flows are computed in 2D for different inlet flow velocities which can reproduce the stable and unstable dynamic regime of the structure. Finally, the comparison between numerical simulations and experiment is investigated.