COMPOUND ENGINE ASSEMBLY WITH CONFINED FIRE ZONE

• US 20160245185A1
• Filed: 09/24/2015
• Published: 08/25/2016
• Est. Priority Date: 02/20/2015
• Status: Active Grant

• Current Assignee: Pratt & Whitney Canada Corporation (Rtx Corporation)
• Original Assignee: Pratt & Whitney Canada Corporation (Rtx Corporation)
• Inventors: USIKOV, Sergey, ZOLOTOV, Andrey, LAMARRE, Sylvain, JULIEN, Andre, GAUL, Michael, THOMASSIN, Jean, MEDVEDEV, Ilya B.
• Granted Patent: US 10,371,060 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: F01C 1/22 of internal-axis type with equidirectional movement of co-operating members at the points of engagement, or with one of the co-operating members being stationary, the inner member having more teeth or tooth- equivalents than the outer member
• CPC Class Codes: F01C 11/008 and of complementary function, e.g. internal combustion engine with supercharger
• 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 6/12 Turbochargers, i.e. plants for augmenting mechanical power output of internal-combustion piston engines by increase of charge pressure
• CPC Class Codes: F02C 7/25 Fire protection or prevention in general A62
• 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: F05D 2220/323 for aircraft propulsion, e.g. jet engines
• CPC Class Codes: F05D 2230/51 in a modular way, e.g. using several identical or complementary parts or features
• CPC Class Codes: F05D 2230/72 Maintenance
• CPC Class Codes: F05D 2250/312 the axes being parallel to each other
• CPC Class Codes: F05D 2260/4031 as in toothed gearing
• CPC Class Codes: F05D 2300/121 Aluminium
• CPC Class Codes: F05D 2300/171 Steel alloys
• CPC Class Codes: F23M 11/02 Preventing emission of flames or hot gases, or admission of air, through working or charging apertures
• CPC Class Codes: Y02T 10/12 Improving ICE efficiencies

Abstract

A compound engine assembly with an engine core including at least one internal combustion engine, a turbine section including a turbine shaft in driving engagement with the engine shaft, and a compressor, and a firewall. The compressor is located on one side of the firewall, and the turbine section and the engine core are located on the other side. The assembly may include a gearbox module with the turbine section and the engine core located on a same side of the gearbox module casing and the compressor located on the opposite side of the gearbox module casing, and with the firewall extending from the gearbox module casing. One or more rotatable accessory may be located on a same side of the firewall as the compressor. A method of reducing fire hazard in a compound engine assembly is also discussed.

Claims

1. A compound engine assembly comprising:

an engine core including at least one internal combustion engine in driving engagement with an engine shaft;

a gearbox module including a gearbox module casing containing at least one gear train;

a turbine section outside of the gearbox module casing, the turbine section having an inlet in fluid communication with an outlet of the engine core, the turbine section including at least one turbine rotor connected to a turbine shaft, the turbine shaft extending into the gearbox module casing and in driving engagement with the engine shaft through one of the at least one gear train of the gearbox module;

a compressor outside of the gearbox module casing, the compressor having an outlet in fluid communication with an inlet of the engine core, the compressor including at least one compressor rotor in driving engagement with at least one of the turbine shaft and the engine shaft;

wherein the turbine section and the engine core are located on a same side of the gearbox module casing and the compressor is located on the opposite side of the gearbox module casing; and

wherein a firewall extends radially outwardly from the gearbox module casing, the compressor being located on one side of the firewall, and the turbine section and the engine core being located on the other side of the firewall.

2. The compound engine assembly as defined in claim 1, wherein the at least one compressor rotor is connected to the turbine shaft, the turbine shaft extending through the gearbox module casing.

3. The compound engine assembly as defined in claim 1, wherein the turbine section is received in a casing of a turbine module, the turbine module being free of electrical elements.

4. The compound engine assembly as defined in claim 1, wherein the firewall is a first firewall, the assembly further including second and third circumferentially spaced apart firewalls extending transversely from the first firewall and a fourth firewall axially spaced apart from the first firewall and extending between the second and third firewalls, the first, second, third and fourth firewalls extending radially outwardly from the engine core and cooperating to define a perimeter surrounding a fuel system of the engine core, the turbine section being located outside of the perimeter.

5. The compound engine assembly as defined in claim 1, further comprising at least one rotatable accessory drivingly engaged to the turbine shaft or to the engine shaft through one of the at least one gear train of the gearbox module, the at least one rotatable accessory being located on the opposite side of the gearbox module casing from the turbine section and the engine core.

6. The compound engine assembly as defined in claim 1, wherein each of the at least one internal combustion engine includes a rotor sealingly and rotationally received within a respective internal cavity to provide rotating chambers of variable volume in the respective internal cavity, the rotor having three apex portions separating the rotating chambers and mounted for eccentric revolutions within the respective internal cavity, the respective internal cavity having an epitrochoid shape with two lobes.

7. The compound engine assembly as defined in claim 1, wherein the turbine section includes a first stage turbine having an inlet in fluid communication with the outlet of the engine core, and a second stage turbine having an inlet in fluid communication with an outlet of the first stage turbine.

8. The compound engine assembly as defined in claim 7, wherein the first stage turbine is configured as an impulse turbine with a pressure-based reaction ratio having a value of at most 0.2, the second stage turbine having a higher reaction ratio than that of the first stage turbine.

9. The compound engine assembly as defined in claim 1, wherein the turbine shaft and the engine shaft are parallel and radially offset from one another.

10. A compound engine assembly comprising:

an engine core including at least one internal combustion engine in driving engagement with an engine shaft;

a turbine module including a turbine section having an inlet in fluid communication with an outlet of the engine core, the turbine section configured to compound power with the engine shaft;

a compressor module including a compressor having an outlet in fluid communication with an inlet of the engine core;

at least one rotatable accessory in driving engagement with the turbine shaft or with the engine shaft;

a firewall extending between the compressor module and the turbine module;

wherein the engine core is located on a same side of the firewall as the turbine module; and

wherein the at least one rotatable accessory is located on a same side of the firewall as the compressor.

11. The compound engine assembly as defined in claim 10, wherein the compressor includes at least one rotor and the turbine section includes at least one rotor, the at least one rotor of the compressor and of the turbine section being connected to a turbine shaft in driving engagement with the engine shaft.

12. The compound engine assembly as defined in claim 10, wherein the turbine section is received in a casing of a turbine module, the turbine module being free of electrical elements.

13. The compound engine assembly as defined in claim 10, wherein the firewall is a first firewall, the assembly further including second and third circumferentially spaced apart firewalls extending transversely from the first firewall and a fourth firewall axially spaced apart from the first firewall and extending between the second and third firewalls, the first, second, third and fourth firewalls extending radially outwardly from the engine core and cooperating to define a perimeter surrounding a fuel system of the engine core, the turbine module being located outside of the perimeter.

14. The compound engine assembly as defined in claim 10, wherein each of the at least one internal combustion engine includes a rotor sealingly and rotationally received within a respective internal cavity to provide rotating chambers of variable volume in the respective internal cavity, the rotor having three apex portions separating the rotating chambers and mounted for eccentric revolutions within the respective internal cavity, the respective internal cavity having an epitrochoid shape with two lobes.

15. The compound engine assembly as defined in claim 10, wherein the turbine section includes a first stage turbine having an inlet in fluid communication with the outlet of the engine core, and a second stage turbine having an inlet in fluid communication with an outlet of the first stage turbine.

16. The compound engine assembly as defined in claim 15, wherein the first stage turbine is configured as an impulse turbine with a pressure-based reaction ratio having a value of at most 0.2, the second stage turbine having a higher reaction ratio than that of the first stage turbine.

17. The compound engine assembly as defined in claim 10, wherein the turbine shaft and the engine shaft are parallel and radially offset from one another, and drivingly engaged to one another.

18. A method of reducing fire hazard in a compound engine assembly, the method comprising:

obstructing fire propagation with a plurality of firewalls, including;

defining a first enclosure with at least one of the firewalls, the first enclosure isolating a fuel system of a core engine of the compound engine assembly from a turbine section, a compressor, and accessories of the compound engine assembly, and

defining a second enclosure with at least one of the firewalls, the second enclosure isolating the turbine section and the core engine of the compound engine assembly from the compressor and the accessories of the compound engine assembly.