Effect of natural frequency of slender structure on VIV at higher reynolds numbers

Abstract

Vortices are formed when a structural element placed in fluid’s flow path. These vortices shed are alternatively, and consequently the structure undergoes vortex-induced vibration in cross-direction. This present study is based on two-dimensional simulation of the vortex-induced vibrations of circular cylinder in an unsteady fluid flow. Aim of the study is to find out the effect of natural frequency of cylinder on its vortex-induced vibration. Smooth circular cylinder is simulated in cross-flow condition using k-ε model of RANS equations in Ansys Fluent. The simulations are carried out for higher Reynolds numbers ranging from 5 × 104 to 50 × 104. The drag and lift force coefficients are found for the cylinder by varying natural frequencies of structure for each Reynolds number in upper subcritical regime. Wake pattern is carefully studied when cylinder is going under cross-flow oscillation, and its dependency on natural frequency of structure is observed. © 2018, Springer Nature Singapore Pte Ltd.