Patent ID: 11959394
Assignee: MITSUBISHI ELECTRIC CORPORATION
Field: Engines, pumps, turbines (Mechanical engineering)
Classification: CPC F | IPC F

Claim 15:
16. The turbine rotor blade according to claim 15,
wherein each of the central fillet portion, the upstream intermediate fillet portion, and the downstream intermediate fillet portion has a cross section demarcated by:
a curved line connecting the suction surface and the upper surface of the platform portion, the curved line being defined by a part of an ellipse;
a first line segment extending from a position where the curved line is connected to the suction surface to the upper surface of the platform portion along a blade height direction; and
a second line segment extending from a position where the first line segment is connected to the upper surface of the platform portion to a position where the curved line is connected to the upper surface,

wherein a curvature radius of the ellipse defining the curved line in the upstream intermediate fillet portion is larger than a curvature radius of the ellipse defining the curved line in the central fillet portion, when compared at a same blade-height-directional position, and
wherein a curvature radius of the ellipse defining the curved line in the downstream intermediate fillet portion is larger than the curvature radius of the ellipse defining the curved line in the central fillet portion, when compared at the same blade-height-directional position.