Study of vortex-shedding-induced vibration of a flexible splitter plate behind a cylinder

A computational analysis of vortex-shedding-induced vibration of a flexible splitter plate behind a cylinder at a low Reynolds number is conducted to understand effects of the length and flexibility of a splitter plate on the drag and lift of a cylinder and vibration of the attached plate. The drag and lift coefficients, the Strouhal number of vortex shedding, and the magnitude of tip displacements of a flexible splitter plate are found to be intricate functions of the plate flexibility. The deflection shape of a flexible splitter plate is dependent on the length of the plate, while the deflection magnitude is a function of the bending stiffness and natural frequencies of the corresponding plate. It is concluded in the present work that the Strouhal number of vortex shedding or the frequency of plate deflection is difficult to estimate using natural frequencies of the plate, which are calculated by inducing free vibration, since the fluid loading is distributed non-uniformly over the plate rather than concentrated at the tip of the plate. The present study suggests that the flexibility of a splitter plate, in general, adversely modulates the drag and lift forces acting on the cylinder surface while it promotes the oscillation of the plate.