Modified Weissinger Lifting Surface Method for Calculating Aerodynamic Parameters of Arbitrary Wing-Canard Configurations

摘要

A digital computer program for calculating lift, induced drag, pitching moment, and span loading of rigid wing-canard configurations in steady flight is presented. The method employed is essentially a modification of the Weissinger L-method. The effect of the canard on the wing is assumed to be due to two counter-rotating viscous-core vortices. The position of the vortices relative to the rear wing is taken into account by superimposing the separate downwash fields of the canard and the wing in an iteration method. The canard is shown to have an adverse effect upon the lift curve slope and induced drag, and to significantly decrease the static margin. In addition, a strong nonlinear pitch-up tendency is found to occur when the trailing vortex from the canard approaches the lower wing surface. (Author)