Gas turbine manufacturers rely on high turbine inlet temperatures to provide boosts to overall engine performance. In typical modern engine applications, gas path temperatures within a turbine section exceed the melting point of the component constituent materials. Due to this, dedicated cooling air is extracted from the compressor, or elsewhere in the turbine engine, and used to cool the gas path components in the turbine.
Another feature implemented within some gas turbine engines is rotating vanes disposed within the flow path of the gas turbine engine. The rotating vanes allow the vane position to be altered in response to varying conditions, thereby improving flow through the gas turbine engine during operation. Rotating vanes (alternately referred to as variable vanes) require extra cooling and high pressure cooling supplies to operate. The need for high pressure cooling air supply becomes largely apparent in the low-pressure implementations of the rotating vane, where the thinner airfoils necessitate a larger supply pressure to accommodate the needed cooling air for the airfoil. This high pressure leads to difficulty in developing cooling configurations for the platforms of the airfoil and dialing back flow losses into the gas-path.
USPTO Backgrounds
USPTO Backgrounds