CALCULATION AND COMPILATION OF THE UNSTEADY-LIFT FUNCTIONS FOR A RIGID WING SUBJECTED TO SINUSOIDAL GUSTS AND TO SINUSOIDAL SINKING OSCILLATIONS

摘要

The total lift responses of wings to sinusoidal gusts and to sinus¬oidal vertical oscillations are calculated from the response to gust penetration and to a sudden change in sinking velocity through use of the well-established reciprocal relations for unsteady flow. The cases con-sidered are two-dimensional wings in incompressible, subsonic compressible, sonic, and supersonic flow; elliptical and rectangular wings in incompressible flow; wide rectangular and delta wings in supersonic flow; and delta wings of vanishingly low aspect ratio in incompressible and compressible flow. For most of the cases considered, closed-form expressions are given and the final results are presented in the form of plots of the square of the modulus of the lift coefficient for wings in a sinusoidally oscillating gust and in the form of the real and imaginary parts of the lift component for wings undergoing sinusoidal sinking oscillations. A summary table is presented as a guide to the scope and results of this paper; this table contains the figure and equation numbers for the types of flow and plan forms considered.