A Clarification of Flow Characteristics around a Tapered Circular Cylinder and Radiated Sound from it in Turbulence

Abstract

In this study, aerodynamic sound generated some tapered cylinders and a circular cylinder under the condition of inflow turbulence are measured. Reynolds number based on tapered cylinder diameter at the mid span and inflow velocity is 2.7 × 10⁴ . The inflow turbulence is generated by using the turbulence grids and it changes to turbulence intensity of 12.6% and 19.1%. The results show that the Aeolian tone reduction is larger for high taper ratio model than circular cylinder but it is small with inflow turbulence. Under the turbulence intensity of 19.1%, the Aeolian tone cannot clearly be observed for both the circular cylinder and the tapered cylinder, and aerodynamic sound increases on broad band in sound spectra.