Patent ID: 11939882
Assignee: MITSUBISHI ELECTRIC CORPORATION
Field: Engines, pumps, turbines (Mechanical engineering)
Classification: CPC F | IPC F

Claim 7:
8. A turbine rotor blade comprising,
a leading edge portion having a plurality of cooling holes,
wherein the plurality of cooling holes includes:
m cooling holes arranged in a first range in a blade height direction, where m is an integer of 2 or more; and
n cooling holes arranged in a second range on a blade tip side of the first range in the blade height direction, where n is an integer of 2 or more, and

wherein n/b<m/a is satisfied, where a is a dimension of the first range in the blade height direction, and b is a dimension of the second range in the blade height direction,
wherein the plurality of cooling holes includes:
a plurality of cooling hole rows each of which is arranged along the blade height direction in the first range; and
at least one cooling hole row which or each of which is arranged along the blade height direction in the second range, and

wherein the number of cooling hole rows in the second range is less than the number of cooling hole rows in the first range,
wherein the number of cooling hole rows in the first range is 3,
wherein the number of cooling hole rows in the second range is 2,
wherein the plurality of cooling hole rows in the first range includes a pressure-side cooling hole row formed on a pressure surface, a suction-side cooling hole row formed on a suction surface, and a middle cooling hole row formed between the pressure-side cooling hole row and the suction-side cooling hole row,
wherein the at least one cooling hole row in the second range includes a pressure-side cooling hole row formed on the pressure surface, and a suction-side cooling hole row formed on the suction surface,
wherein the pressure-side cooling hole row in the first range is arranged along a first virtual line which is linear,
wherein the suction-side cooling hole row in the first range is arranged along a second virtual line which is linear,
wherein the middle cooling hole row is arranged along a third virtual line which is linear, and
wherein when
X is defined as a distance between the first virtual line and the second virtual line at a same position in the blade height direction on the blade surface,
Y is defined as a distance between the second virtual line and the third virtual line at a same position in the blade height direction on the blade surface,
Ymax is defined as a maximum value of the distance Y in the first range, and
h1 is defined as a position in the blade height direction such that the distance X is less than the distance Ymax,

the second range is located between the position h1 and the blade tip.