Patent ID: 7246482

Claim:
A gas turbine engine system, comprising: an engine case; a high pressure turbine and a low pressure turbine disposed in flow series within the engine case, the high pressure turbine and low pressure turbine mounted on a high pressure spool and a low pressure spool, respectively, each spool rotationally mounted within the engine case; a generator having an input shaft coupled to the high pressure spool to receive a drive force therefrom; a bleed air conduit having an inlet port, an outlet port, and a flow passage therebetween, the bleed air conduit inlet port fluidly coupled between the high pressure and low pressure turbines to receive a flow of bleed air from the high pressure turbine; a flow control valve mounted on the bleed air conduit and selectively movable between at least a closed position, in which the bleed air conduit inlet port is fluidly isolated from the bleed air conduit outlet port, and an open position, in which the bleed air conduit inlet port is in fluid communication with the bleed air conduit outlet port; a heat exchanger having at least a first fluid flow path coupled in series-fluid communication in the bleed air flow passage, the heat exchanger operable to transfer heat from the bleed air to a cooling fluid; and an air turbine having a fluid inlet and a rotationally mounted output shaft, the air turbine fluid inlet in fluid communication with the bleed air conduit outlet port to receive bleed air therefrom when the flow control valve is in the open position, the air turbine output shaft coupled to the generator.