Patent ID: 8820091

Claim:
A gas turbine engine comprising: a compressor section where air pulled into the engine is compressed; a combustion section where fuel is mixed with at least a portion of the compressed air from the compressor section and burned to create hot combustion gases; a turbine section where the hot combustion gases from the combustion section are expanded to extract energy therefrom, wherein at least a portion of the extracted energy is used to rotate a turbine rotor during a first mode of engine operation comprising full load operation; a rotor chamber in communication with structure to be cooled within the turbine section; at least one rotor cooling pipe that injects cooling air extracted from the engine into the rotor chamber during the first mode of engine operation; and a cooling fluid injection system comprising: a source of external cooling fluid to be injected into the rotor chamber only during a second mode of engine operation comprising less than full load operation; the at least one rotor cooling pipe, which is used to inject cooling fluid from the external cooling fluid source into the rotor chamber during the second mode of engine operation; a piping system that provides fluid communication between the external cooling fluid source and the at least one rotor cooling pipe; a blower system for conveying cooling fluid from the external cooling fluid source through the piping system and the at least one rotor cooling pipe into the rotor chamber; and a valve system that is: closed during the first mode of engine operation to prevent cooling fluid from the external cooling fluid source from being conveyed through the piping system by the blower system; and open during the second mode of engine operation to allow cooling fluid from the external cooling fluid source to be conveyed through the piping system by the blower system.