METHOD FOR COOLING A GAS TURBINE AND GAS TURBINE FOR CONDUCTING SAID METHOD

摘要

A method is disclosed for cooling a gas turbine having a turbine, wherein a rotor, which rotates about a machine axis, carries a plurality of rotating blades, which are mounted by blade roots and extend with their airfoils into a hot gas path of the gas turbine. The rotor is concentrically surrounded by a turbine vane carrier carrying a plurality of stationary vanes, whereby the rotating blades and the stationary vanes are arranged in alternating rows in axial direction. An extended lifetime with external cooling is achieved by providing first and second cooling systems for the turbine.

主权项

1. Method for cooling a gas turbine, which includes a turbine, wherein a rotor, which rotates about a machine axis, carries a plurality of rotating blades, which are mounted on said rotor by blade roots and extend with their airfoils into a hot gas path of said gas turbine, wherein said rotor is concentrically surrounded by a turbine vane carrier carrying a plurality of stationary vanes, whereby said rotating blades and said stationary vanes are arranged in alternating rows in axial direction, the method comprising:
providing first and second cooling systems (A, B) for said turbine, whereby said first cooling system (A) uses cooling air of a first pressure and first temperature and said second cooling system (B) uses cooling air of a second pressure and second temperature substantially smaller than said first pressure and first temperature, and whereby said first cooling system (A) is used to cool the airfoils of said rotating blades and said turbine vane carrier and said stationary vanes, and whereby said second cooling system (B) is used to cool said rotor and said blade roots of said rotating blades in at least one row of said rotating blades.