Transition piece, combustor provided with same, and gas turbine provided with combustor

A transition piece demarcating a periphery of a combustion gas flow path where combustion gas flows from an upstream side to a downstream side in an axial direction in which an axis extends, wherein:

• a plurality of cooling passages which extend in the axial direction and inside which a cooling medium flows are formed so as to be aligned in the axial direction and a circumferential direction with regard to the axis;
• one or more downstream side passages which are a portion of the plurality of cooling passages are formed in a downstream side region on the downstream side within at least one circumferential region in the circumferential direction, and one or more upstream side passages which are another portion of the plurality of cooling passages are formed in an upstream side region on the upstream side with regard to the downstream side region within the circumferential region;
• a total cross-sectional area per unit circumferential length of the one or more downstream side passages in the downstream side region is greater than a total cross-sectional area per unit circumferential length of the one or more upstream side passages in the upstream side region;
• and
• a cross-sectional area of the downstream side passage is larger than a cross-sectional area of the upstream side passage.

A transition piece demarcating a periphery of a combustion gas flow path where combustion gas flows from an upstream side to a downstream side in an axial direction in which an axis extends, wherein:

• a plurality of cooling passages which extend in the axial direction and inside which a cooling medium flows are formed so as to be aligned in the axial direction and a circumferential direction with regard to the axis;
• one or more downstream side passages which are a portion of the plurality of cooling passages are formed in a downstream side region on the downstream side within at least one circumferential region in the circumferential direction, and one or more upstream side passages which are another portion of the plurality of cooling passages are formed in an upstream side region on the upstream side with regard to the downstream side region within the circumferential region;
• a total cross-sectional area per unit circumferential length of the one or more downstream side passages in the downstream side region is greater than a total cross-sectional area per unit circumferential length of the one or more upstream side passages in the upstream side region;
• and
• an inlet is formed at a first end portion of the plurality of cooling passages, and an outlet is formed at a second end portion of the plurality of cooling passages.

A transition piece demarcating a periphery of a combustion gas flow path where combustion gas flows from an upstream side to a downstream side in an axial direction in which an axis extends, wherein:

• a plurality of cooling passages which extend in the axial direction and inside which a cooling medium flows are formed so as to be aligned in the axial direction and a circumferential direction with regard to the axis;
• one or more downstream side passages which are a portion of the plurality of cooling passages are formed in a downstream side region on the downstream side within at least one circumferential region in the circumferential direction, and one or more upstream side passages which are another portion of the plurality of cooling passages are formed in an upstream side region on the upstream side with regard to the downstream side region within the circumferential region;
• and
• a ratio of a cross-sectional area of the downstream side passage to a length in the axial direction of the downstream side passage is larger than a ratio of a cross-sectional area of the upstream side passage to a length in the axial direction of the upstream side passage.

A transition piece provided in a gas turbine casing that covers a gas turbine rotor and demarcating a periphery of a combustion gas flow path where combustion gas flows from an upstream side to a downstream side in an axial direction in which an axis extends, wherein:

• a plurality of cooling passages which extend in the axial direction and inside which a cooling medium flows are formed so as to be aligned in a circumferential direction with regard to the axis;
• one or more rotor side passages which are a portion of the plurality of cooling passages are formed in a rotor side region opposing the gas turbine rotor within at least one axial region in the axial direction, and one or more casing side passages which are another portion of the plurality of cooling passages are formed in a casing side region opposing an inner circumferential surface of the gas turbine casing within the axial region;
• and
• a total cross-sectional area per unit circumferential length of the one or more casing side passages in the casing side region is greater than a total cross-sectional area per unit circumferential length of the one or more rotor side passages in the rotor side region.

A transition piece provided in a gas turbine casing that covers a gas turbine rotor and demarcating a periphery of a combustion gas flow path where combustion gas flows from an upstream side to a downstream side in an axial direction in which an axis extends, wherein:

• a plurality of cooling passages which extend in the axial direction and inside which a cooling medium flows are formed so as to be aligned in a circumferential direction with regard to the axis;
• one or more rotor side passages which are a portion of the plurality of cooling passages are formed in a rotor side region opposing the gas turbine rotor within at least one axial region in the axial direction, and one or more casing side passages which are another portion of the plurality of cooling passages are formed in a casing side region opposing an inner circumferential surface of the gas turbine casing within the axial region;
• and
• a ratio of a cross-sectional area of the casing side passage to a length in the axial direction of the casing side passage is larger than a ratio of a cross-sectional area of the rotor side passage to a length in the axial direction of the rotor side passage.