A gas turbine is provided and includes a compressor, which via an air intake inducts and compresses air; a combustion chamber, in which a fuel is combusted using the compressed air, producing a hot gas; and a turbine, equipped with turbine blades, in which the hot gas is expanded, performing work. A first device is provided in order to cool turbine blades with compressed cooling air. The first device includes at least one separate compressor stage which produces compressed cooling air independently of the compressor.
1. A gas turbine, comprising:
a compressor, which via an air intake inducts and compresses air;
a combustion chamber in which a fuel is combusted, using the compressed air, producing a hot gas;
a turbine, equipped with turbine blades, in which the hot gas is expanded; and
at least one separate compressor, which produces compressed cooling air independently of the compressor, and wherein the compressed cooling air from the at least one separate compressor cools the turbine blades, wherein the at least one separate compressor arranged directly aft of the last turbine rotor blades in the flow direction, the at least one separate compressor inducts a cooling air mass flow from a rotor-bearing plenum, and the at least one separate compressor delivers a main mass flow compressed cooling air to the last turbine rotor blades for cooling purposes, and wherein the at least one separate compressor delivers a partial mass flow of compressed cooling air for the purging of a sealing gap between the rotor or shaft and an adjoining stationary part of the gas turbine.
2. The gas turbine as claimed in claim 1 , wherein the turbine has a rotor or a shaft, and the at least one separate compressor is integrated into the rotor or into the shaft.
3. The gas turbine as claimed in claim 1 , wherein the at least one separate compressor is a radial compressor.
4. The gas turbine as claimed in claim 1 , wherein the at least one separate compressor has an outer shroud, and the partial mass flow is delivered through an exit point in the shroud.
5. A gas turbine, comprising:
a compressor, which via an air intake inducts and compresses air;
a combustion chamber in which a fuel is combusted, using the compressed air, producing a hot gas;
a turbine, equipped with turbine blades, in which the hot gas is expanded; and
at least one separate compressor, which produces compressed cooling air independently of the compressor, and wherein the compressed cooling air from the at least one separate compressor cools the turbine blades, wherein the at least one separate compressor arranged directly aft of the last turbine rotor blades in the flow direction, the at least one separate compressor inducts a cooling air mass flow from a rotor-bearing plenum, and the at least one separate compressor delivers a main mass flow compressed cooling air to the last turbine rotor blades for cooling purposes, and wherein the main mass flow at the exit of the at least one separate compressor is deflected from a radial direction into an axial direction, and in that the rotor or the shaft is provided with an exit radius where deflection from a radial direction to an axial direction occurs.
6. The gas turbine as claimed in claim 5 , wherein the turbine has a rotor or a shaft, and the at least one separate compressor is integrated into the rotor or into the shaft.
7. The gas turbine as claimed in claim 5 , wherein the at least one separate compressor is a radial compressor.