Asymptotic Expansion of the Kernel Function in Subsonic Unsteady Lifting Surface Theory

Abstract

A computer oriented asymptotic expansion of a singular integral function is presented. The function dealt with appears in the kernel of the integral equation which is solved for pressure distributions of subsonic unsteady lifting surfaces. Values of the function can be accurately computed in short times by using the present expansion. The expansion series includes terms which are calculated with the aid of a recurrence formula. Every singular part is, however, explicitly written as an initial term. Other approximations are evaluated by comparing them with the present results.