GAS TURBINE ENGINE AND AIRCRAFT WITH A GAS TURBINE ENGINE

Abstract

A gas turbine engine for an aircraft comprising an engine core and including a bypass channel which radially surrounds the engine core at least in part is described. A core shaft is operatively connected to an engine accessory gearbox, which is arranged between the engine core and the bypass channel, by means of a radial shaft of a drive train. An electric machine is provided which is designed to start the gas turbine engine during motor operation and to generate electrical energy during alternator operation. The electric machine is arranged coaxially with the core shaft and connected thereto for conjoint rotation. Alternatively, the electric machine can be arranged radially outside the bypass channel and can be operatively connected to the core shaft by means of the radial shaft, wherein a rotor of the electric machine is arranged coaxially with the radial shaft and connected thereto for conjoint rotation.

Claims

1. A gas turbine engine, comprising an engine core and comprising a bypass channel which radially surrounds the engine core at least in part, wherein a core shaft extending in the axial direction is operatively connected to an engine accessory gearbox which is arranged between the engine core and the bypass channel by means of a radial shaft of a drive train, wherein an electric machine is provided which is designed to start the gas turbine engine during motor operation and to generate electrical energy during alternator operation, wherein the electric machine is arranged coaxially with the core shaft and is connected thereto for conjoint rotation or is arranged radially outside the bypass channel and is operatively connected to the core shaft by means of the radial shaft, and wherein a rotor of the electric machine is arranged coaxially with the radial shaft and is connected thereto for conjoint rotation.

2. The gas turbine engine according to claim 1, wherein the rotor is rotatably mounted in a stator of the electric machine.

3. The gas turbine engine according to claim 1, wherein engine accessories are substantially operatively connected to the drive train by means of the engine accessory gearbox, which engine accessories are provided to carry out functions of the gas turbine engine and are arranged between the engine core and the bypass channel.

4. The gas turbine engine according to claim 1, wherein the electric machine is designed to substantially supply electrical energy to aircraft accessories which are provided to carry out functions of an aircraft which is configured with the gas turbine engine.

5. The gas turbine engine according to claim 4, wherein the aircraft accessories are arranged radially outside the bypass channel.

6. The gas turbine engine according to claim 1, wherein the electric machine is arranged in the circumferential direction at least in part in a region of the gas turbine engine in which the gas turbine engine comprises means which are designed to connect the gas turbine engine to an aircraft, the region of the gas turbine engine overlapping a fuselage of the aircraft when the engine is installed on the aircraft.

7. The gas turbine engine according to claim 1, wherein the engine accessory gearbox is designed to transmit a torque and to drive an oil pump, a fuel pump, an air/oil separator and/or a permanent magnet alternator.

8. The gas turbine engine according to claim 4, wherein an electrically operable hydraulic pump is an aircraft accessory, is arranged radially outside the bypass channel, is operatively connected to the electric machine and can receive electrical energy therefrom.

9. The gas turbine engine according to claim 1, wherein the engine accessory gearbox is arranged in the axial direction in the region of a rear side of a front engine frame between the engine core and the bypass channel.

10. An aircraft, comprising at least one gas turbine engine according to claim 1, wherein the gas turbine engine is arranged on the fuselage or in the fuselage of the aircraft, and wherein the electric machine is arranged in a region of overlap between the gas turbine engine and the fuselage radially outside the bypass channel.

11. The aircraft according to claim 10, wherein the electric machine is arranged radially in an engine nacelle, in part radially in the engine nacelle and in part radially outside the engine nacelle in an engine pylon and/or the fuselage or radially outside the engine nacelle in the engine pylon and/or in the fuselage.

12. The aircraft according to claim 10, wherein the electric machine is arranged so as to be radially aligned with the radial shaft in the engine nacelle, in the engine pylon and/or in the fuselage.

Description

[0059] It is self-evident to a person skilled in the art that a feature or parameter described in relation to one of the above aspects can be applied to any other aspect, unless they are mutually exclusive. Furthermore, any feature or any parameter described here may be applied to any aspect and/or combined with any other feature or parameter described, unless they are mutually exclusive. Further advantages and advantageous developments of the invention can be found in the claims and the exemplary embodiments described based on the concept with reference to the drawings,

[0060] in which:

[0061] FIG. 1 is a simplified three-dimensional view of an aircraft with gas turbine engines arranged in the rear region on an aircraft fuselage;

[0062] FIG. 2 is a simplified longitudinal sectional view of a gas turbine engine of the aircraft according to FIG. 1;

[0063] FIG. 3 is a simplified cross-sectional view of the gas turbine engine according to FIG. 2; and

[0064] FIG. 4 shows an illustration corresponding to that of FIG. 3 of another embodiment of the gas turbine engine according to FIG. 2.

[0065] FIG. 1 shows an aircraft or a passenger aircraft 1 which has three gas turbine engines 2, 3, 4. The first gas turbine engine 2 is arranged on a left-hand side of the aircraft in the rear region of the aircraft 1, in the region of a vertical stabilizer 6, and is attached in the region of an engine pylon 7 to a fuselage 8 of the aircraft 1. The second gas turbine engine 3 is connected to the fuselage 8 substantially mirror-symmetrically on a right-hand side of the aircraft.

[0066] The third gas turbine engine 4 is positioned at the rear end of the fuselage 8 and is attached to an inner fuselage strut, which is arranged below the vertical stabilizer 6 of the aircraft 1. An air inlet 10 is provided to supply air to the third gas turbine engine 4. The air inlet 10 is arranged, in front of the vertical stabilizer 6 in a direction of flight, on a top side of the fuselage 8 and is connected, within the aircraft fuselage 8, to the third gas turbine engine 4.

[0067] FIG. 2 is a simplified longitudinal sectional view of the gas turbine engine 2 of the aircraft 1 according to FIG. 1. The gas turbine engine 2 comprises a subsidiary flow channel or bypass channel 11 and an inlet region 12. Downstream of the inlet region 12, a blower 13 is connected in a manner which is known per se.

[0068] After the blower 13, the fluid flow in the gas turbine engine 2 is divided into a bypass flow and a core flow. The bypass flow flows through the bypass channel 11, whereas the core flow flows into an engine core 14. The engine core 14 is configured with a compressor device 15, with a burner 16, with a low-pressure turbine 17 which is provided to drive the blower 13, and with a high-pressure turbine 18 provided to drive the compressor device 15.

[0069] In addition, FIG. 2 is a schematic view of an engine accessory gearbox 19 which is arranged substantially in the region of an intermediate casing 20 of the gas turbine engine 2. The intermediate casing 20 is located in the radial direction R of the gas turbine engine 2 in a region between the engine core 14 and the bypass channel 11.

[0070] Furthermore, an electric machine 39 is provided radially outside the bypass channel 11. The electric machine 39 can be operated both as a motor and as an alternator so as to be able to start the gas turbine engine 2 and to generate electrical energy in the operation of the gas turbine engine 2. By means of the electrical energy of the electric machine 39, which is what is known as a starter alternator of the gas turbine engine, for example an electric hydraulic pump and an on-board network of the aircraft 1 can be operated.

[0071] The engine accessory gearbox 19 and the electric machine 39 are driven by a radial shaft 22 of a drive train 9 which is operatively connected to a core shaft 24 of the gas turbine engine 2, which core shaft extends in the axial direction A of the gas turbine engine 2. The radial shaft 22 is connected to the core shaft 24 by means of an angle drive 5. In the present case, the core shaft 24 is a high-pressure shaft of the gas turbine engine 2 which, in the operation of the gas turbine engine 2, rotates at a higher speed than another core shaft 23 arranged coaxially therewith which is what is known as a low-pressure shaft.

[0072] Starting from the core shaft 24, the radial shaft 22 extends substantially in the radial direction R of the gas turbine engine 2 through what is known as an inner strut 25, that is to say a strut formed with a hollow profile or an aerodynamic profile formed with a hollow profile, outwards through the engine core 14 to the intermediate casing 20. In the region of the intermediate casing 20, the radial shaft 22 interacts with a drive shaft 27 by means of another angle drive 26 in the form of a bevel gear set.

[0073] By means of gear pairs 30 of the engine accessory gearbox 19, which in the present case are in the form of spur-gear stages, the drive shaft 27 is connected to what are known as engine accessories 28. In the present case, the engine accessories 28 are an air/oil separator, an oil pump, a fuel pump, a permanent-magnet alternator and other accessories which are provided for the operation of the gas turbine engine 2. The oil pump supplies the gas turbine engine 2 with oil for lubrication and cooling. In addition, in the intermediate casing 20, an oil tank and an oil cooler which can be temperature-controlled by fuel are also arranged radially inside the bypass channel 11 in the gas turbine engine 2.

[0074] The electric machine 39 is arranged radially in an engine nacelle 29 which is delimited radially outwardly by an outer side of the engine nacelle 29 and radially inwardly by an outer side 31 of the bypass channel 11. Starting from the intermediate casing 20, the radial shaft 22 extends inside an outer strut 40 radially through the bypass channel 11 as far as the electric machine 39. The electric machine 39 is arranged coaxially with the radial shaft 22 and so as to be radially aligned therewith. This means that a rotor 33 of the electric machine 39 which is connected to the radial shaft 22 for conjoint rotation rotates about the longitudinal axis of the radial shaft 22. Furthermore, the rotor 33 is rotatably mounted on a stator 34 of the electric machine 39.

[0075] FIG. 2 also shows another electric machine 39A which is arranged radially inside the engine core 14 and has the same range of functions as the electric machine 39. In this case, it is provided that the gas turbine engine 2 is configured either with the electric machine 39 radially outside the bypass channel 11 or with the electric machine 39A radially inside the engine core 14. In the case of the embodiment of the gas turbine engine 2 in which the electric machine 39A is arranged radially inside the engine core 14, the radial shaft 22 extends in the radial direction R only between the angle drive 5 and the other angle drive 26. That is to say that the radial shaft 22 is then not guided radially outwards through the bypass channel 11.

[0076] The electric machine 39A is arranged coaxially with the core shaft 24. In this case, the rotor 33A of the electric machine 39A is connected to the core shaft 24 for conjoint rotation so as to be able to introduce a corresponding torque into the core shaft 24 in the motor operation of the electric machine 39A when starting the gas turbine engine 2. At the same time, in the alternator operation of the electric machine 39A, the rotor 33A can be driven by the core shaft 24 by means of the connection to the core shaft 24 for conjoint rotation in order to generate electrical energy. The rotor 33A is arranged radially inside the stator 34A and rotatably mounted thereon.

[0077] According to the present application in each case, it can also be provided that the engine accessory gearbox 19 is operatively connected to the other core shaft 23. Irrespective thereof, the electric machine 39A is operatively connected to the core shaft 24 in order to allow the gas turbine engine 2 to be started by the electric machine 39A.

[0078] FIG. 3 is a simplified cross-sectional view of the embodiment of the gas turbine engine 2 according to FIG. 2, in which the electric machine 39 is arranged radially outside the bypass channel 11 and even radially outside the engine nacelle 29 in the engine pylon 7. In the present case, an electrically drivable hydraulic pump 32 is what is known as an aircraft accessory.

[0079] In the exemplary embodiment of the gas turbine engine 2 shown in FIG. 3, the engine accessory gearbox 19 is arranged together with the engine accessories radially between the bypass channel 11 and the engine core 14. In the present case, the engine accessories are inter alia the previously mentioned fuel pump 35, the air/oil separator or a breather 36 and the oil pump 37. Furthermore, a fuel metering unit 38 (FMU), a measuring nozzle for controlling the amount of fuel which arrives at the burner 16, a fuel filter and an oil filter, an oil tank 41 and an oil cooler 42 which can be temperature controlled by means of fuel are also provided on the engine core 14 so as to be distributed in the circumferential direction U.

[0080] FIG. 4 shows the embodiment of the gas turbine engine 2 in which the electric machine 39A is arranged radially inside the engine core 14 and is directly connected to the core shaft 24.

LIST OF REFERENCE SIGNS

[0081] 1 Aircraft [0082] 2 to 4 Gas turbine engine [0083] 5 Angle drive [0084] 6 Vertical stabilizer [0085] 7 Engine pylon [0086] 8 Fuselage [0087] 9 Drive train [0088] 10 Air inlet [0089] 11 Bypass channel [0090] 12 Inlet region [0091] 13 Blower [0092] 14 Engine core [0093] 15 Compressor device [0094] 16 Burner [0095] 17 Low-pressure turbine [0096] 18 High-pressure turbine [0097] 19 Engine accessory gearbox [0098] 20 Intermediate casing [0099] 22 Radial shaft [0100] 23 Core shaft, low-pressure shaft [0101] 24 Core shaft, high-pressure shaft [0102] 25 Inner strut [0103] 26 Additional angle drive [0104] 27 Drive shaft [0105] 28 Engine accessory [0106] 29 Engine nacelle [0107] 30 Gear pair [0108] 31 Outer side of the bypass channel [0109] 32 Hydraulic pump [0110] 33, 33A Rotor [0111] 34, 34A Stator [0112] 35 Fuel pump [0113] 36 Air/oil separator [0114] 37 Oil pump [0115] 38 Fuel metering unit [0116] 39, 39A Electric machine [0117] 40 Outer strut [0118] 41 Oil tank [0119] 42 Oil cooler [0120] A Axial direction [0121] R Radial direction of the gas turbine engine [0122] U Circumferential direction