US 6,305,156 B1 · Integrated bleed air and engine starting system

Abstract

An integrated bleed air and engine starting system for an engine utilizes an innovative flow multiplier air turbine starter to provide bleed air supply to an ECS as well as starting an engine. The technique reduces bleed air consumption by mixing fan stage air and high stage air for ECS fresh air usage. It also can eliminate or reduce the size of the precooler heat exchanger. The system includes an air turbine starter subsystem and an air flow subsystem. The air turbine starter subsystem includes a compressor, a turbine, and a common shaft fixed between the compressor and turbine. Also provided is a gear coupled to a gearbox which links the engine with a shaft, as well as a variable nozzle valve intermediate the turbine and engine. The air flow subsystem comprises a diverter valve downstream of the turbine, an isolation valve intermediate the turbine and an auxiliary power unit, and a check valve downstream of the compressor and turbine. A fan is in air flow communication with the compressor and engine.

Claims17

Dependent claims

An integrated bleed air and engine starting system for an engine, comprising:

an air turbine starter subsystem comprising a turbine mechanically coupled to said engine, a compressor mechanically coupled to said turbine, and a variable nozzle upstream of said turbine;
said variable nozzle having an open position that allows said bleed air to flow to said turbine;
and
an air flow subsystem that includes a diverter valve downstream of said turbine and an isolation valve upstream of said variable nozzle;
said diverter valve having a feed position that flows to an environmental control system a mixture of an exhaust from said turbine with a compressed air from said compressor;
whereby said air flow subsystem selectively directs said bleed air through said variable nozzle and to said turbine or through said isolation valve, around said turbine, and to said environmental control system, said air flow subsystem also enables an auxiliary air flow from an auxiliary power unit to flow to said isolation valve and be selectively received by said turbine.

3 more elements

An integrated bleed air and engine starting system for an engine, comprising:

an air turbine starter subsystem comprising a compressor, a turbine coupled to said compressor and engine, and a variable nozzle intermediate said turbine and engine;
said variable nozzle having an open position in a first bleed air mode of said engine that allows said bleed air to flow to said turbine and said variable nozzle having a closed position in a second bleed air mode of said engine that precludes said bleed air from flowing to said turbine;
a fan in air flow communication with said compressor and engine;
and
an air flow subsystem that includes a diverter valve downstream of said turbine and an isolation valve upstream of said variable nozzle;
said diverter valve having a feed position in said first bleed air mode that feeds an exhaust from said turbine mixed with a compressed air from said compressor to an environmental control system and said diverter valve having an overboard position in an engine start mode of said engine that flows said turbine exhaust mixed with said compressed air out of said air flow subsystem;
said isolation valve having a closed position in said first bleed air mode an open position in said second bleed air mode, and said open position in said engine start mode;
whereby said air flow subsystem selectively directs said bleed air through said turbine in said first bleed air mode and engine start mode or around said turbine and to said environmental control system in said second bleed air mode, said air flow subsystem also enables an auxiliary air flow from an auxiliary power unit to be selectively received by said turbine in said engine start mode.

5 more elements

Dependencies are inferred from the claim text.

Integrated bleed air and engine starting system

Life of this patent

Integrated bleed air and engine starting system

Life of this patent

Abstract

Claims17