WebOct 6, 2004 · Typically, side edge fences can achieve a noise reduction of up to 4 dB in the middle to high frequency domain in which flaps are known to be major noise sources. In this paper, we discuss the mechanisms that cause this reduction and present an analytical model for studying these mechanisms. WebFlap edge noise reduction fins . United States Patent 9132909 . Abstract: A flap of the type that is movably connected to an aircraft wing to provide control of an aircraft in flight includes opposite ends, wherein at least a first opposite end includes a plurality of substantially rigid, laterally extending protrusions that are spaced apart to ...
Flap Edge Noise Reduction Fins - NASA Technical Reports …
WebJul 5, 2024 · Abstract Besides the investigation of the aeroacoustics responses of an asymmetric aerofoil subjected to serrated trailing edge flap angles from negative (flap-down) to positive (flap-up), this paper also provides a new perspective on the physical mechanisms of broadband noise reduction by a serrated trailing edge. The blade … WebJun 1, 2014 · Finally, the Flap Edge Noise Reduction Fins (FENoRFins) design 12 is an array of densely packed comb like structures (fins) in a 3-D arrangement extending inward in the spanwise direction from... danger threats dcf
Flap Side Edge Liners for Airframe Noise Reduction - Tech Briefs
WebApr 7, 2024 · The flap side-edge is a vital contributor to airframe noise. In this study, we propose a novel flap side-edge noise reduction method based on the concept of active blowing air. A long slot is opened from the flap’s lower surface to the tip surface to induce a secondary jet flow, which is driven by the local pressure difference between the … WebNov 19, 2024 · The most promising tip treatment tested was the trailing edge (TE) notch at a radial location of 0.95 r /R with a double slot width and a double depth (DSDD). The … WebSep 1, 2015 · Flap Edge Noise Reduction Fins (FENoRFins) are modifications consisting of rigid fins on the edges of the aircraft flaps. The open-structure nature of each flap … birmingham watch company