Turbine disk and gas turbine

A gas turbine in which compressed air compressed in a compressor is combusted by supplying fuel thereto in a combustor, and a combustion gas thus generated is supplied to a turbine to obtain rotation drive power, wherein

• the turbine comprises a turbine disk that is rotatably supported;
• and a plurality of rotor blades arranged on an outer circumference of the turbine disk in a circumferential direction, and having a cooling passage inside,
• the turbine disk includes:
• a plurality of first cooling holes that penetrates the turbine disk from inside toward outside thereof in a radial direction of the turbine disk, is communicatively connected to the cooling passage, and is arranged in the circumferential direction;
• and
• a plurality of second cooling holes that are arranged between each of the first cooling holes, and penetrates the turbine disk from the inside toward the outside thereof in a radial direction of the turbine disk, wherein
• base ends of the first cooling holes and the second cooling holes are configured to receive cooling gas,
• leading ends of the first cooling holes and the second cooling holes are communicatively connected to a radial direction communicating channel arranged in the circumferential direction,
• a plurality of fitting grooves arranged on an outer circumference in the circumferential direction are fitted with respective fitting protrusions on the rotor blades to form axial direction communicating channels in spaces between the fitting grooves and the rotor blades along an axial direction,
• the first cooling holes are arranged correspondingly to the axial direction communicating channels in the circumferential direction, and the leading ends thereof are communicatively connected to the radial direction communicating channel and the axial direction communicating channels, and
• the second cooling holes are arranged between the first cooling holes in the circumferential direction, and have the leading ends sealed, and are communicatively connected to the radial direction communicating channel.