CONSTRUCTING SECTION PROFILE CURVE OF TURBINE BLADE

With the development of aero manufacturing, Precise description of turbine blade is required. The shape of leading/trailing edge is very important to the section profile curve of the turbine blade. Generally, the leading/trailing edge is a small section of the elliptic arc. In order to model the blade accurately, we propose here a new idea of handling the difficult situation where the noised data span a small section of the elliptic arc. This new fitting algorithm based on the fitting ellipses subject to the constraint of length of semi-minor axis is presented to extract the important parameters of leading edge and trailing edge at first. The discrete data points of cross-section profile curve are interpolated with G2 continuous rational Bezier curves. Leading edge and trailing edge are described as rational Bezier curves precisely. Finally, the results of experiments demonstrate the effectiveness of the method for constructing a globe faired section profile curve of turbine blade.