Abstract: A first bent portion bent toward an intrados and a second bent portion located in the rear of the first bent portion and bent toward an extrados are provided on a camber line on a trailing edge in the rear of 90% of a chord length of a turbine blade having an extremely low aspect ratio for an axial-flow turbine. The inclination of the camber line immediately in the rear of the second bent portion on the side of a blade root is substantially equal to the inclination of the camber line immediately in front of the first bent portion, and the curvature of the second bent portion is decreased from the side of the blade root toward a blade tip. As a result, a higher-pressure portion on the intrados which is a pressure surface of the turbine blade is displaced toward the trailing edge, and thus a secondary flow from the side of the blade tip toward the blade root can be suppressed, whereby a pressure loss particularly in the vicinity of the blade root can be suppressed to the minimum.

Abstract: A first bent portion bent toward an intrados and a second bent portion located in the rear of the first bent portion and bent toward an extrados are provided on a camber line on a trailing edge in the rear of 90% of a chord length of a turbine blade having an extremely low aspect ratio for an axial-flow turbine. The inclination of the camber line immediately in the rear of the second bent portion on the side of a blade root is substantially equal to the inclination of the camber line immediately in front of the first bent portion, and the curvature of the second bent portion is decreased from the side of the blade root toward a blade tip. As a result, a higher-pressure portion on the intrados which is a pressure surface of the turbine blade is displaced toward the trailing edge, and thus a secondary flow from the side of the blade tip toward the blade root can be suppressed, whereby a pressure loss particularly in the vicinity of the blade root can be suppressed to the minimum.