Influence of Attached Splitter Plate on the Flow and Flow-induced Noise Generated from Circular Cylinder

doi:10.3901/JME.2024.12.287

Abstract

Abstract: The characteristics of flow and aerodynamic noise generated around a circular cylinder using an attached splitter plate with different lengths (no more than cylinder diameter) have been studied and compared with the circular cylinder case of the same characteristic dimensions at a Reynolds number of 6×10⁴ based on the theory of vortex sound and acoustic analogy approach after the flow is simulated using the delayed detached-eddy model. The calculated spectra of far-field aerodynamic noise agree well with the anechoic wind-tunnel experiments for the circular cylinder case, verifying the accuracy of the numerical simulations. Results show that the developing of the vortex shedding induced from the flow separations is limited along two sides of the splitter plate after it is attached at the rear of the cylinder. The separated shear layer developed in the wake of cylindrical bars is elongated and the dissipation of vortex motion is strengthened. The vortex undulation close to the walls and regular vortex shedding in the wake are mitigated. Thus the strength of near-field quadrupole sound source is reduced. Meanwhile the aerodynamic force fluctuation and mean drag are decreased. Consequently the harmonic peak values of flow-induced noise generated from the vortex shedding are reduced effectively and the corresponding amplitude of sound pressure level of far-field dipole sound source is decreased. Thereby a good aerodynamic noise reduction effect is achieved for a circular cylinder with an attached splitter plate.

Key words: circular cylinder, splitter plate, aerodynamic noise, flow behaviour, noise control

CLC Number:

O355

ZHU Jianyue, YUAN Yongyi, CHEN Yu, XU Junqi. Influence of Attached Splitter Plate on the Flow and Flow-induced Noise Generated from Circular Cylinder[J]. Journal of Mechanical Engineering, 2024, 60(12): 287-300.

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