Effects of Blowing Location on Aeroacoustics of the Flow over a Circular Cylinder

Abstract

This study investigated the effect of blowing on vortex shedding and aerodynamic noise due to flow over a circular cylinder. The flow simulation is performed by the URANS equations using k-ω-SST turbulence model. Calculations of the aerodynamic noise are performed through F-fowcs Williams-Hawkins analogy. The cylinder's cross-section with a diameter of D=16mm, and the blowing jet is applied through slot windows that are located on the cylinder back surface. In this study, three positions for slot windows are considered. Verification of the numerical results is confirmed by comparing numerical results with the reported experimental ones (Uncontrolled case). The results showed that the optimal blowing position could reduce noise, lift coefficient, and drag coefficient; this result occurs for a slot window located near the cylinder horizontal axis of symmetry. On the other hand, if the blowing slot is located at the cylinder symmetric vertical axis, the aerodynamic noise increases by approximately 4 dB. In this case, the average lift and drag fluctuations are increased by more than 200%. The present study gives a new idea to the reduction of noise of the single body systems.