Extension of the Theory of Oscillating Airfoils of Finite Span in Subsonic Compressible Flow

As part of an investigation of flows around and forces on an oscillating finite wing in subsonic compressible flow, the exact double integrals occurring in the theoretical formulation of the three-dimensional nonstationary aerodynamic forces have previously been reduced to single integrals over the range of either one of the two independent variables. The present report describes a method for solving the resultant three-dimensional problem based on a generalization of approximate methods for solving two-dimensional problems. It is shown that the calculation of three-dimensional corrections to the two-dimensional integral equation for spanwise variation of circulation, provided tabulated values for the kernal of the integral equation are available.