Alternative Derivation for an Intergral Equation for Linearized Subsonic Flow Over a Wing.

摘要

An integral equation for the time dependent linearized subsonic flow over a wing has been derived in a previous report by K. G. Guderley and Maxwell Blair (AD-A 176 684). The present alternative derivation due to Marc H. Williams is presented. The difference lies in the sequence of events. The original derivation was carried out in a coordinate system moving with the wing. Williams' derivation makes the crucial step in a coordinate fixed in the undisturbed air and then carries out a transformation to wing coordinates. In addition, this derivation clarifies the relation between the integral equation for steady and unsteady flow, and derives a formulation based on the Lorentz transform. Keywords: Subsonic flow; Time dependence; Unsteady aerodynamics; Integral equations. (edc)