| 摘要 |
PURPOSE: To enhance the performance of a turbine blade and facilitate assembly by positioning the driving center of the root part of each blade in proximity in vertical direction to a plane surrounding the inlet face of a platform part and allowing the thickness of the boundary layer along the convex surface of the blade to remain small. CONSTITUTION: The airfoil part of a turbine blade is composed of a front edge 18, rear edge 20, convex negative pressure surface 22, and concave positive pressure surface 24, wherein the radius of curvature of the convex surface 22 increases at a constant rate from the front edge 18 to the rear edge 20. Thereby the stream decelerates till the neck part of the airfoil, and a constant flow velocity is generated in the region downstream of the neck part. The driving center of the root part is positioned at Point A or in its neighborhood. Point A is positioned in proximity to the plane surrounding the inlet face 26 of the platform part, apart approx. 0.79 inch in X-Y direction away from the inlet face 26, and this distance is substantially identical to the distance between the inlet face 18 of the airfoil and the inlet face 26 of the platform part. |
