Defence Technology (Mar 2024)
Research on the flow stability and noise reduction characteristics of quasi-periodic elastic support skin
Abstract
To enhance flow stability and reduce hydrodynamic noise caused by fluctuating pressure, a quasi-periodic elastic support skin composed of flexible walls and elastic support elements is proposed for fluid noise reduction. The arrangement of the elastic support element is determined by the equivalent periodic distance and quasi-periodic coefficient. In this paper, a dynamic model of skin in a fluid environment is established. The influence of equivalent periodic distance and quasi-periodic coefficient on flow stability is investigated. The results suggest that arranging the elastic support elements in accordance with the quasi-periodic law can effectively enhance flow stability. Meanwhile, the hydrodynamic noise calculation results demonstrate that the skin exhibits excellent noise reduction performance, with reductions of 10 dB in the streamwise direction, 11 dB in the spanwise direction, and 10 dB in the normal direction. The results also demonstrate that the stability analysis method can serve as a diagnostic tool for flow fields and guide the design of noise reduction structures.