THE EFFECT OF DIHEDRAL ON THE AERODYNAMIC DERIVATIVES WITH RESPECT TO SIDESLIP FOR AIRFOILS IN SUPERSONIC FLOW

• Published in: Quarterly journal of mechanics and applied mathematics 1956, Vol.9 (4), p.425-440
• Main Author: POWELL, J. B. L.
• Format: Article
• Language: English
• ISSN: 0033-5614; 1464-3855
• DOI: 10.1093/qjmam/9.4.425

A thin dihedral wing in supersonio flow is given a small velocity in sideslip. By a linearized theory the surface pressure distribution is investigated for wings whose planform is symmetrical about the line of undisturbed flow through the vertex. This involves dividing the problem into two parts, depending on whether the wing leading edges lie outside or inside the Mach cone from their vertex. For each case the force derivatives are determined and graphs are exhibited which give the value of these derivatives for wings of delta planform. For other wing shapes graphs are shown which give the contribution from the interference pressure alone. For a delta wing it is found that to a good approximation the rolling derivative varies with the sine of the angle of dihedral and the yawing and sideslip derivatives vary with the square of the sine of this angle. As the values of the derivatives at small dihedral are known explicitly, this provides a useful method for obtaining the values at more general dihedral angles.