국내 최대 기계 및 로봇 연구정보

공학설계D/B

공학설계D/B 게시판 내용
Volume Title	Aerodynamics
Volume No	BODIES - Drag (continued)
DATA Title	Effect of stabilising fins on base drag of cylindrical bodies at supersonic speeds.
DATA Item	97022
KEYWORD	axisymmetric, base, body, combination, cruciform, cylinder, drag, fin, interference, missile, supersonic, wing
ISBN	1 86246 024 8
ABSTRACT	ESDU 97022 gives a method for estimating the increment in (jet off) base drag, over that for the body alone given by ESDU 79022, due to stabilising fins on axisymmetric cylindrical bodies at zero angle of attack with a turbulent boundary layer at Mach numbers from 1.5 to 5. It is based on a simple theoretical model modified with an empirical factor to fit wind-tunnel data and was derived for cruciform or planar fins mounted with trailing-edges flush with the base or upstream of the base. It may be applied to up to six equally-spaced fins. The fins tested were of circular-arc or diamond section with maximum thickness at mid-chord but the method can be applied to other configurations. The method requires at least three body diameters of cylindrical body length upstream of the fins to ensure there is no forebody/fin interference. Sketches compare the predictions with the experimental results and show the increment is predicted to within 0.01in base drag coefficient based on base area. Details of geometries used in the correlation are provided, and a fully worked example illustrates the use of the method.