국내 최대 기계 및 로봇 연구정보

기술보고서

기술보고서 게시판 내용
타이틀	Aeroacoustic Study of a High-Fidelity Aircraft Model Part 2;; Unsteady Surface Pressures
저자	Khorrami, Mehdi R.;; Neuhart, Danny H.
Keyword	AEROACOUSTICS;; AERODYNAMIC NOISE;; AIRCRAFT NOISE;; CIVIL AVIATION;; GENERAL AVIATION AIRCRAFT;; LANDING GEAR;; MACH NUMBER;; NOISE REDUCTION;; PRESSURE MEASUREMENT;; PRESSURE OSCILLATIONS;; SUBSONIC WIND TUNNELS;; UNDERCARRIAGES;; WIND TUNNEL TESTS
URL	http://hdl.handle.net/2060/20120010350
보고서번호	NF1676L-13779
발행년도	2012
출처	NTRS (NASA Technical Report Server)
ABSTRACT	In this paper, we present unsteady surface pressure measurements for an 18%-scale, semi-span Gulfstream aircraft model. This high-fidelity model is being used to perform detailed studies of airframe noise associated with main landing gear, flap components, and gear-flap interaction noise, as well as to evaluate novel noise reduction concepts. The aerodynamic segment of the tests, conducted in the NASA Langley Research Center 14- by 22-Foot Subsonic Tunnel, was completed in November 2010. To discern the characteristics of the surface pressure fluctuations in the vicinity of the prominent noise sources, unsteady sensors were installed on the inboard and outboard flap edges, and on the main gear wheels, struts, and door. Various configurations were tested, including flap deflections of 0?, 20?, and 39?, with and without the main landing gear. The majority of unsteady surface pressure measurements were acquired for the nominal landing configuration where the main gear was deployed and the flap was deflected 39?. To assess the Mach number variation of the surface pressure amplitudes, measurements were obtained at Mach numbers of 0.16, 0.20, and 0.24. Comparison of the unsteady surface pressures with the main gear on and off shows significant interaction between the gear wake and the inboard flap edge, resulting in higher amplitude fluctuations when the gear is present.