Aeroelastic Problems of Low Aspect Ratio Wings: Part III. Aerodynamic Forces on an Oscillating Delta Wing

Abstract

For a delta wing it is not sufficient to consider spanwise bending and chordwise rotation only. Chordwise bending must be added. It is therefore necessary to calculate the aerodynamic coefficients accordingly. The theory of Lawrence and Gerber dealing with aerodynamic coefficients of oscillating delta wings in incompressible flow is extended to give the coefficients at any station of the wing. It is shown that for practical reasons the assumption is made that induction may be neglected. This means that the coefficients are theoretically only correct for a rigid wing in pitching and plunging. However they will be used for a flexible wing with spanwise bending, chordwise bending and rotation. For the oscillating delta wing with subsonic leading edges in supersonic flow the theory of Watkins and Berman will be discussed. Here again the original report is extended to give the coefficients at any station of the wing. The calculation of the natural modes of vibration of the wing, based on the methods of Scanlan and Rosenbaum, is presented for completeness. Finally it is shown how the coefficients and the modes may be combined to give the aerodynamic forces. As an appendix the differences between the British and the American techniques for calculating the aerodynamic coefficients are discussed.

Citation

Leyds, J. (1956), "Aeroelastic Problems of Low Aspect Ratio Wings: Part III. Aerodynamic Forces on an Oscillating Delta Wing", Aircraft Engineering and Aerospace Technology, Vol. 28 No. 4, pp. 119-122. https://doi.org/10.1108/eb032680