PURPOSE: To avoid generation of a shock wave in the case of a high subsonic speed or ultrasonic wave so as to realize high efficiency by forming curvature distribution on a blade back side of a blade row in such a manner as to once have a minimum value within a range from a blade front edge toward a blade rear edge and then have a maximum value.
CONSTITUTION: A moving blade row to be turned together with a plurality of stationary blade rows is disposed at the inner surface of a casing constituting an annular passage. In curvature distribution of a blade back side from the blade front edge of the stationary blade row toward the blade rear edge thereof, a curve 3a is drawn from the blade front edge in such a manner as to once have a minimum value 3b and then a maximum value 3c. The maximum value 3b is located between a position having a Mach number of 1 at the blade surface and a position of a maximum speed, and the maximum value 3c is positioned in a region of a maximum speed on the blade back side. With this blade structure, in the case where fluid having a subsonic flow speed is supplied to the blade front edge, the fluid having a speed exceeding a sonic speed and supplied from the blade rear edge is set at a subsonic speed on the blade back side.
TSUDA YOSHIHIRO
YANAGIDA MITSUAKI
TORITANI HAJIME
SASADA TETSUO
