REVERSE-FLOW GAS TURBINE ENGINE

• US 20180073428A1
• Filed: 09/15/2016
• Published: 03/15/2018
• Est. Priority Date: 09/15/2016
• Status: Active Grant

• Current Assignee: Pratt & Whitney Canada Corporation (Raytheon Technologies Corporation d/b/a RTX)
• Original Assignee: Pratt & Whitney Canada Corporation (Raytheon Technologies Corporation d/b/a RTX)
• Inventors: MORGAN, Keith, PELUSO, Robert, PLANTE, Ghislain, GEKHT, Eugene, DUROCHER, Eric, DUBREUIL, Jean
• Granted Patent: US 11,415,063 B2
• Time in Patent Office: Days
• CPC Class Codes: F01D 1/26 traversed by the working-fluid substantially axially
• CPC Class Codes: F02C 3/04 having a turbine driving a compressor power transmission arrangements F02C7/36; control of working fluid flow F02C9/16
• CPC Class Codes: F02C 3/067 having counter-rotating rotors F02C3/073 takes precedence
• CPC Class Codes: F02C 3/113 with variable power transmission between rotors
• CPC Class Codes: F02C 3/145 the combustion chamber being in the reverse flow-type
• CPC Class Codes: F02C 6/206 the vehicles being airscrew driven
• CPC Class Codes: F02C 7/04 Air intakes for gas-turbine plants or jet-propulsion plants
• CPC Class Codes: F02C 7/32 Arrangement, mounting, or driving, of auxiliaries
• CPC Class Codes: F02C 7/36 Power transmission arrangements between the different shafts of the gas turbine plant, or between the gas-turbine plant and the power user F02C3/107 - F02C3/13 and F02C7/32 take precedence; couplings for transmitting rotation F16D; gearing in general F16H
• CPC Class Codes: F04D 25/024 the driving means being assisted by a power recovery turbine
• CPC Class Codes: F05D 2220/32 in gas turbines
• CPC Class Codes: F05D 2250/38 angled, e.g. sweep angle
• CPC Class Codes: F05D 2260/40 Transmission of power
• CPC Class Codes: Y02T 50/60 Efficient propulsion technologies, e.g. for aircraft

Abstract

A gas turbine engine has a first spool having a low pressure compressor section disposed forward of an air inlet along a direction of travel of the engine, and a low pressure turbine section disposed forward of the low pressure compressor section and drivingly engaged thereto. A second spool has a high pressure compressor section disposed forward of the low pressure compressor section, and a high pressure turbine section disposed forward of the high pressure compressor section and drivingly engaged thereto. The high pressure turbine section is disposed aft of the low pressure turbine section. An output drive shaft drivingly engages the low pressure turbine section and extends forwardly therefrom to drive a rotatable load. A method of operating a gas turbine engine is also discussed.

Claims

1. A gas turbine engine, comprising:

a first spool having a low pressure compressor section disposed forward of an air inlet along a direction of travel of the engine and in fluid communication with the air inlet, and a low pressure turbine section disposed forward of the low pressure compressor section and drivingly engaged thereto;

a second spool having a high pressure compressor section disposed forward of the low pressure compressor section and in fluid communication therewith to receive pressurized air therefrom, and a high pressure turbine section disposed forward of the high pressure compressor section and drivingly engaged thereto, the high pressure turbine section disposed aft of the low pressure turbine section and in fluid communication therewith; and

an output drive shaft drivingly engaged to the low pressure turbine section and extending forwardly therefrom, the drive shaft configurable to drivingly engage a rotatable load disposed forward of the low pressure turbine section.

2. The engine as defined in claim 1, wherein the first spool includes a power shaft extending between the low pressure compressor section and the low pressure turbine section, the power shaft and the drive shaft being co-axial and interconnected.

3. The engine as defined in claim 1, further comprising an accessory gearbox disposed aft of the air inlet, a tower shaft mechanically coupled to a high pressure shaft extending between the high pressure compressor section and the high pressure turbine section, and an accessory gear box drive shaft having a first end mechanically coupled to the tower shaft and a second end mechanically coupled to the accessory gearbox.

4. The engine as defined in claim 3, wherein the accessory gear box drive shaft extends across the air inlet.

5. The engine as defined in claim 1, further comprising an inter-stage bleed disposed aft of the high pressure compressor section and forward of the low pressure compressor section.

6. The engine as defined in claim 1, wherein the drive shaft has a first segment extending between the low pressure compressor section and the low pressure turbine section, and a second segment extending forwardly from the low pressure turbine section to drivingly engage the rotatable load.

7. The engine as defined in claim 1, wherein the rotatable load includes a propeller, and the engine is a turboprop engine.

8. A method of operating a gas turbine engine, comprising:

drawing air into a core of the engine through a low pressure compressor section and then through a high pressure compressor section along a forward direction with respect to a direction of travel of the engine to provide pressurized air;

igniting a mixture of the pressurized air and fuel to generate combustion gases;

circulating the combustion gases along the forward direction through a high pressure turbine section and then through a low pressure turbine section to drive the high pressure and low pressure turbine sections with the combustion gases;

driving the high pressure compressor section with the high pressure turbine section; and

driving the low pressure compressor section and a rotatable load with the low pressure turbine section, the low pressure turbine section and the high pressure turbine section rotating independently from one another.

9. The method as defined in claim 8, wherein driving the low pressure compressor section and the rotatable load includes rotating a drive shaft driving the rotatable load and the low pressure compressor section at a same rotational speed.

10. The method as defined in claim 8, wherein driving the high pressure compressor section includes rotating the high pressure compressor section at a first rotational speed, and driving the low pressure compressor section includes rotating the low pressure compressor section at a second rotational speed different from the first rotational speed.

11. The method as defined in claim 8, further comprising driving an accessory gearbox with the high pressure turbine section, the accessory gearbox disposed aft of an air inlet in fluid communication with the low pressure compressor section.

12. The method as defined in claim 11, wherein driving the accessory gearbox includes driving an accessory gear box drive shaft extending across the air inlet.

13. The method as defined in claim 8, further comprising bleeding pressurized air from the core of the engine at a location disposed aft of the high pressure compressor section and forward of the low pressure compressor section.

14. The method as defined in claim 8, wherein driving the rotatable load includes driving a propeller through a reduction gear box.

15. A gas turbine engine, comprising:

an output drive shaft having a front end configurable to drivingly engage a rotatable load;

a low pressure turbine section and a low pressure compressor section drivingly engaged to the drive shaft, the low pressure turbine section disposed forward of the low pressure compressor section;

a high pressure shaft rotatable independently of the drive shaft;

a high pressure turbine section and a high pressure compressor section drivingly engaged to the high pressure shaft, the high pressure compressor section disposed forward of the low pressure compressor section and in fluid communication therewith, and the high pressure turbine section disposed aft of the low pressure turbine section and in fluid communication therewith;

wherein during operation of the engine, air flows toward the front end of the drive shaft through the low pressure and high pressure compressor sections, and combustion gases flow toward the front end of the drive shaft through the high pressure and low pressure turbine sections.

16. The engine as defined in claim 15, further comprising a power shaft mechanically coupled to the drive shaft, the power shaft extending between the low pressure turbine section and the low pressure compressor section.

17. The engine as defined in claim 15, further comprising an accessory gearbox disposed aft of the low pressure compressor section, a tower shaft mechanically coupled to the high pressure shaft, and an accessory gear box drive shaft having a first end mechanically coupled to the tower shaft and a second end mechanically coupled to the accessory gearbox.

18. The engine as defined in claim 17, wherein the accessory gear box drive shaft extends across an air inlet communicating with the low pressure compressor section.

19. The engine as defined in claim 15, further comprising an inter-stage bleed disposed aft of the high pressure compressor section and forward of the low pressure compressor section.

20. The engine as defined in claim 15, wherein the drive shaft is configurable to drivingly engage the rotatable load including a propeller, and the engine is a turboprop engine.