Correlation of Experimental Aerodynamic Coefficients on the Basis of Curve Fitting in the Three-Dimensional Cartesian alpha, (C sub N), (C sub m) Space.

摘要

A method is presented for curve fitting experimental aerodynamic normal-force and pitching-moment coefficient data as a function of angle of attack. The method is based on the postulation of the existence of a single (C sub N)-(C sub m)-alpha space curve that has a common offset value of the angle of attack for which the normal-force and pitching-moment coefficients simultaneously vanish. The curve fits in the (C sub N)-(alpha) and (C sub m)-(alpha) planes are based on minimizing the squared error between the fitted curves and the experimental data by proper selection of the curve-fit coefficients and the common angle-of-attack offset value. (Author)