Numerical Study on Aeroelastic Instability of a Rectangular Cylinder in Heaving Oscillations

Abstract

The unsteady three-dimensional flows around a forced-oscillating or freely oscillating rectangular cylinder are numerically simulated by means of the direct finite difference method without any turbulence model. We discuss the accuracy of the present method for prediction of unsteady aerodynamic forces and responses to various dynamic properties. First we examine the aerodynamic forces in case of forced oscillation with D/B = 2 of a rectangular cylinder through the comparison with experiments. Also, in order to understand fundamental behaviors of unstable oscillations of a rectangular cylinder, which is elastically mounted in heaving mode in uniform flow, the effect of various dynamic parameters such as mass ratio, damping ratio or the Scruton number, on aeroelastic instabilities is individually investigated.