The effect of fins on vortex shedding from a cylinder in cross-flow

A bare tube and three segmented-finned tubes have been tested to investigate the effect of the fins on vortex shedding from cylinders in cross-flow. The addition of the fins is found to enhance the process of vortex shedding. It is shown that the fins increase the correlation length and the amplitude of velocity fluctuation at the vortex shedding frequency. The fins also increase the nonlinear nature of the flow in the wake, as evidenced by a remarkable increase in the number and in the amplitude of the higher harmonic components of vortex shedding. However, the correlation length in the wake of the finned tubes is found to change with angular rotation of the tube around its axis. This phenomenon seems to be related to an irregular wavy pattern of the fin distribution along the tube axis.