A sealing air bypass flow path is provided in a gas turbine for supplying sealing air to a sealing air supply flow path by bypassing the flow path between each tangential on board injection (TOBI) nozzles and disk holes.
1. A gas turbine comprising:
a plurality of stationary blades disposed in a circle;
a plurality of moving blades disposed in a circle on a rotor disk side adjacent to these stationary blades;
a seal disk coaxially connected to the upstream side of the rotor disk;
a first TOBI nozzle that supplies bleed air to the seal disk as a swirling flow which rotates in the same direction as the seal disk;
a sealing air supply flow path that communicates with a discharge port of the first TOBI nozzle and supplies sealing air to a space between the stationary blades and the moving blades;
a disk hole provided in the seal disk for flowing the swirling flow; and
a sealing air bypass flow path provided for supplying the sealing air to the sealing air supply flow path by bypassing the flow path between the first TOBI nozzle and the disk hole, wherein a second TOBI nozzle is provided for taking up a portion of the bleed air, forming swirling flow, and controlling a rate of flow of the sealing air to the sealing air bypass flow path.