Patent ID: 7300247

Claim:
An axial flow turbine, comprising: a casing; and a plurality of stages, provided in the casing, comprising turbine nozzles and turbine blades, respectively, wherein both ends of the nozzles of each stages are supported between a diaphragm inner ring and a diaphragm outer ring, the turbine nozzles having nozzle blades; wherein a flow passage in the stages is formed with a diameter expanded from an upstream side to a downstream side, trailing edges of at least one of the nozzles are curved as a curvature to an outlet side of the flow passage around both ends thereof, and an intermediate portion between both ends of the trailing edge is formed to be straight, and a center of the nozzle blade in a direction of a height is set as a position of a maximum value of a throat pitch ratio between the trailing edge of the nozzle blade and a back side of the adjacent nozzle blade.