국내 최대 기계 및 로봇 연구정보

기술보고서

기술보고서 게시판 내용
타이틀	TRANSONIC FLIGHT TEST OF A LAMINAR FLOW LEADING EDGE WITH SURFACE EXCRESCENCES
저자	Fanny A. Zuniga, Aaron Drake, Robert A. Kennelly, Jr., Dennis J. Koga and Russell V. Westphal
Keyword	Boundary-layer transition; Hot films; Laminar flow; Stanton gauge measurements; Surface excrescences
URL	http://www.dfrc.nasa.gov/DTRS/1994/PDF/H-1994.pdf
보고서번호	NASA-TM-4597
발행년도	1994
출처	NASA Dryden Flight Research Center
ABSTRACT	A flight experiment, conducted at NASA Dryden Flight Research Center, investigated the effects of surface excrescences, specifically gaps and steps, on boundary-layer transition in the vicinity of a leading edge at transonic flight conditions. A natural laminar flow leading-edge model was designed for this experiment with a spanwise slot manufactured into the leading-edge model to simulate gaps and steps like those present at skin joints of small transonic aircraft wings. The leading-edge model was flown with the flight test fixture, a low-aspect ratio fin mounted beneath an F-104G aircraft. Test points were obtained over a unit Reynolds number range of 1.5 to 2.5 million/ft and a Mach number range of 0.5 to 0.8. Results for a smooth surface showed that laminar flow extended to approximately 12 in. behind the leading edge at Mach number 0.7 over a unit Reynolds number range of 1.5 to 2.0 million/ft. The maximum size of the gap-and-step configuration over which laminar flow was maintained consisted of two 0.06-in. gaps with a 0.02-in. step at a unit Reynolds number of 1.5 million/ft.