P.R. Ashill, J.L. Fulker, A. Shires

This paper describes a theoretical study into the use of a novel method to control shock strength of Natural Laminar Flow aerofoil sections. The method uses active control of a flexible skin on the upper surface of the aerofoil, extending either side of the shock wave above the aerofoil. The skin is deflected outwards by up to 0.4% chord, so that it induces compression waves in the flow upstream of the shock wave. These compression waves reduce the strength of the shock wave in the flowfield and consequently reduce wave drag. Calculations made using a Computational Fluid Dynamics (CFD) code for transonic aerofoils show that reductions in drag of up to about 20% are possible for flexible surfaces of length 20% chord, without either a significant increase in viscous drag or a change in pitching moment. It is also shown that use of the flexible surface increases lift coefficient for buffet onset at the design Mach number.

First European Forum on Laminar Flow Technology, Hamburg, 1992

Conference Paper

englisch

21,0 x 29,7 cm, 9 Seiten

DGLR-Bericht, 1992, 1992-06, First European Forum on Laminar Flow Technology; S.175-183; 1992; Deutsche Gesellschaft für Luft- und Raumfahrt - Lilienthal-Oberth e.V., Bonn

NA

aerodynamics, laminar flow, shock waves

Bestellbar

1992