WO2014143074A1 - Geared architecture with inducer for gas turbine engine - Google Patents

Geared architecture with inducer for gas turbine engine Download PDF

Info

Publication number
WO2014143074A1
WO2014143074A1 PCT/US2013/033960 US2013033960W WO2014143074A1 WO 2014143074 A1 WO2014143074 A1 WO 2014143074A1 US 2013033960 W US2013033960 W US 2013033960W WO 2014143074 A1 WO2014143074 A1 WO 2014143074A1
Authority
WO
WIPO (PCT)
Prior art keywords
inducer
gas turbine
fan
compressor
turbine engine
Prior art date
Application number
PCT/US2013/033960
Other languages
French (fr)
Inventor
Daniel Bernard KUPRATIS
Frederick M. Schwarz
Original Assignee
United Technologies Corporation
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by United Technologies Corporation filed Critical United Technologies Corporation
Priority to EP13877780.0A priority Critical patent/EP2834505B1/en
Publication of WO2014143074A1 publication Critical patent/WO2014143074A1/en

Links

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02C—GAS-TURBINE PLANTS; AIR INTAKES FOR JET-PROPULSION PLANTS; CONTROLLING FUEL SUPPLY IN AIR-BREATHING JET-PROPULSION PLANTS
    • F02C7/00—Features, components parts, details or accessories, not provided for in, or of interest apart form groups F02C1/00 - F02C6/00; Air intakes for jet-propulsion plants
    • F02C7/36—Power transmission arrangements between the different shafts of the gas turbine plant, or between the gas-turbine plant and the power user
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02K—JET-PROPULSION PLANTS
    • F02K3/00—Plants including a gas turbine driving a compressor or a ducted fan
    • F02K3/02—Plants including a gas turbine driving a compressor or a ducted fan in which part of the working fluid by-passes the turbine and combustion chamber
    • F02K3/04—Plants including a gas turbine driving a compressor or a ducted fan in which part of the working fluid by-passes the turbine and combustion chamber the plant including ducted fans, i.e. fans with high volume, low pressure outputs, for augmenting the jet thrust, e.g. of double-flow type
    • F02K3/06—Plants including a gas turbine driving a compressor or a ducted fan in which part of the working fluid by-passes the turbine and combustion chamber the plant including ducted fans, i.e. fans with high volume, low pressure outputs, for augmenting the jet thrust, e.g. of double-flow type with front fan
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
    • F05D—INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
    • F05D2260/00—Function
    • F05D2260/40—Transmission of power
    • F05D2260/403—Transmission of power through the shape of the drive components
    • F05D2260/4031—Transmission of power through the shape of the drive components as in toothed gearing
    • F05D2260/40311—Transmission of power through the shape of the drive components as in toothed gearing of the epicyclical, planetary or differential type

Definitions

  • This disclosure relates to a geared architecture for a gas turbine engine.
  • One type of geared turbofan engine includes a two-spool arrangement in which a low spool, which supports a low pressure turbine section, is coupled to a fan via a planetary gear train.
  • a high pressure spool supports a high pressure turbine section.
  • Low and high pressure compressor sections are respectively supported by the low and high spools.
  • the planetary gear train includes a planetary gear set surrounding and intermeshing with a centrally located sun gear that is connected to the low spool.
  • a ring gear circumscribes and intermeshes with the planetary gears.
  • a fan shaft supports the fan. The fan shaft is connected to either the planetary gears or the ring gear, and the other of the planetary gears and ring gear is grounded to the engine static structure.
  • This type of planetary gear arrangement can limit the design speeds of and configuration of stages in the low and high pressure turbine sections.
  • a gas turbine engine includes first and second shafts rotatable about a common axis.
  • a first turbine section is supported on the first shaft.
  • Second compressor and turbine sections are supported on the second shaft.
  • the gas turbine engine includes a fan.
  • a first compressor section is arranged in an axial flow relationship with the second compressor and the first and second turbines.
  • a geared architecture operatively connects the first shaft and the fan.
  • An inducer operative couples to the gear train.
  • the gas turbine engine includes a bypass flow path and a core flow path.
  • the first and second compressor and turbine sections are arranged in the core flow path, and the fan extends into the bypass flow path.
  • the inducer is arranged in the core flow path outside of the bypass flow path and upstream from the first compressor section.
  • first and second shafts respectively provide low and high spools.
  • the first compressor and turbine sections are low pressure compressor and turbine sections.
  • the second compressor and turbine sections are high pressure compressor and turbine sections.
  • the geared architecture includes first and second gear trains.
  • the first gear train is an epicyclic gear train, and the second gear train is configured to provide a speed reduction.
  • the inducer is coupled to the first gear train.
  • the epicyclic gear train is a differential gear train that includes a sun gear. Planetary gears are arranged about and intermesh with the sun gear. A ring gear circumscribes and intermeshes with the planetary gears.
  • the inducer is rotationally fixed relative to the ring gear.
  • the inducer is rotationally fixed relative to the star gear.
  • the inducer is coupled to the second gear train.
  • the inducer is rotationally fixed relative to the fan.
  • the inducer is configured to rotate at a different rotational speed than the first compressor section.
  • the inducer is configured to rotate at a different rotational speed than the fan.
  • the inducer is configured to rotate at a different rotational speed than the fan.
  • a gas turbine engine includes first and second shafts rotatable about a common axis.
  • a first turbine section is supported on the first shaft.
  • Second compressor and turbine sections are supported on the second shaft.
  • the gas turbine engine includes a fan.
  • a first compressor section is arranged in an axial flow relationship with the second compressor and the first and second turbines.
  • a geared architecture operatively connects the first shaft and the fan.
  • An inducer is operatively coupled to the gear train.
  • the gas turbine engine includes a bypass flow path and a core flow path.
  • the first and second compressor and turbine sections are arranged in the core flow path, and the fan extends into the bypass flow path.
  • the inducer is arranged in the core flow path outside of the bypass flow path and upstream from the first compressor section.
  • First and second shafts respectively provide low and high spools.
  • the first compressor and turbine sections are low pressure compressor and turbine sections, and the second compressor and turbine sections are high pressure compressor and turbine sections.
  • the geared architecture includes first and second gear trains.
  • the first gear train is an epicyclic gear train, and the second gear train is configured to provide a speed reduction.
  • the inducer is coupled to the first gear train.
  • the epicyclic gear train is a differential gear train that includes a sun gear. Planetary gears are arranged about and intermesh with the sun gear. A ring gear circumscribes and intermeshes with the planetary gears.
  • the inducer is rotationally fixed relative to the ring gear.
  • the inducer is rotationally fixed relative to the star gear.
  • the inducer is coupled to the second gear train.
  • the inducer is rotationally fixed relative to the fan.
  • the inducer is configured to rotate at a different rotational speed than the first compressor section.
  • the inducer is configured to rotate at a different rotational speed than the fan.
  • the inducer is configured to rotate at a different rotational speed than the fan.
  • Figure 1 schematically illustrates a gas turbine engine embodiment.
  • Figure 2 is a schematic view of a geared architecture embodiment for the engine shown in Figure 1.
  • Figure 3 is a schematic view of another geared architecture embodiment.
  • Figure 4 is a schematic view of a geared architecture embodiment with an inducer.
  • Figure 5 is a schematic view of yet another geared architecture embodiment.
  • Figure 6 is a schematic view of another geared architecture embodiment with an inducer.
  • Figure 7 is a schematic view of yet another geared architecture embodiment with an inducer.
  • Figure 8 is a schematic view of still another geared architecture embodiment with an inducer.
  • Figure 9A is a schematic view of an epicyclic gear train having a first example geometry ratio.
  • Figure 9B is a schematic view of an epicyclic gear train having a second example geometry ratio.
  • Figure 9C is a schematic view of an epicyclic gear train having a third example geometry ratio.
  • Figure 10 is a nomograph depicting the interrelationship of speeds of epicyclic gear train components for a given geometry ratio.
  • Figure 11A is a schematic view of an epicyclic gear train having the first geometry ratio with a carrier rotating in the opposite direction to that shown in Figure 9A.
  • Figure 11B is a schematic view of an epicyclic gear train having the second geometry ratio with a carrier rotating in the opposite direction to that shown in Figure 9B.
  • Figure 11C is a schematic view of an epicyclic gear train having the third geometry ratio with a carrier rotating in the opposite direction to that shown in Figure 9C.
  • FIG. 1 schematically illustrates a gas turbine engine 20.
  • the gas turbine engine 20 is disclosed herein as a two-spool turbofan that generally incorporates a fan section 22, a compressor section 24, a combustor section 26 and a turbine section 28.
  • Alternative engines might include an augmentor section (not shown) among other systems or features.
  • the fan section 22 drives air along a bypass flowpath B while the compressor section 24 drives air along a core flowpath C for compression and communication into the combustor section 26 then expansion through the turbine section 28.
  • FIG. 1 schematically illustrates a gas turbine engine 20.
  • the gas turbine engine 20 is disclosed herein as a two-spool turbofan that generally incorporates a fan section 22, a compressor section 24, a combustor section 26 and a turbine section 28.
  • Alternative engines might include an augmentor section (not shown) among other systems or features.
  • the fan section 22 drives air along a bypass flowpath B while the compressor section 24 drives air along a core flowpath C for compression and communication into the comb
  • the engine 20 generally includes a low speed spool 30 and a high speed spool 32 mounted for rotation about an engine central longitudinal axis A relative to an engine static structure 36 via several bearing systems 38. It should be understood that various bearing systems 38 at various locations may alternatively or additionally be provided.
  • the low speed spool 30 generally includes an inner shaft 40 that interconnects a fan 42, a low pressure (or first) compressor section 44 and a low pressure (or first) turbine section 46.
  • the inner shaft 40 is connected to the fan 42 through a geared architecture 48 to drive the fan 42 at a lower speed than the low speed spool 30.
  • the high speed spool 32 includes an outer shaft 50 that interconnects a high pressure (or second) compressor section 52 and high pressure (or second) turbine section 54.
  • a combustor 56 is arranged between the high pressure compressor 52 and the high pressure turbine 54.
  • a mid- turbine frame 57 of the engine static structure 36 is arranged generally between the high pressure turbine 54 and the low pressure turbine 46.
  • the mid-turbine frame 57 supports one or more bearing systems 38 in the turbine section 28.
  • the inner shaft 40 and the outer shaft 50 are concentric and rotate via bearing systems 38 about the engine central longitudinal axis A, which is collinear with their longitudinal axes.
  • a "high pressure" compressor or turbine experiences a higher pressure than a corresponding "low pressure” compressor or turbine.
  • the core airflow C is compressed by the low pressure compressor 44 then the high pressure compressor 52, mixed and burned with fuel in the combustor 56, then expanded over the high pressure turbine 54 and low pressure turbine 46.
  • the mid-turbine frame 57 includes airfoils 59 which are in the core airflow path.
  • the turbines 46, 54 rotationally drive the respective low speed spool 30 and high speed spool 32 in response to the expansion.
  • the engine 20 in one example is a high-bypass geared aircraft engine.
  • the engine 20 bypass ratio is greater than about six (6), with an example embodiment being greater than ten (10)
  • the geared architecture 48 is an epicyclic gear train, such as a star gear system or other gear system, with a gear reduction ratio of greater than about 2.3 and the low pressure turbine 46 has a pressure ratio that is greater than about 5.
  • the engine 20 bypass ratio is greater than about ten (10: 1)
  • the fan diameter is significantly larger than that of the low pressure compressor 44
  • the low pressure turbine 46 has a pressure ratio that is greater than about 5: 1.
  • Low pressure turbine 46 pressure ratio is pressure measured prior to inlet of low pressure turbine 46 as related to the pressure at the outlet of the low pressure turbine 46 prior to an exhaust nozzle. It should be understood, however, that the above parameters are only exemplary of one embodiment of a geared architecture engine and that the present invention is applicable to other gas turbine engines including direct drive turbofans.
  • a significant amount of thrust is provided by the bypass flow B due to the high bypass ratio.
  • the fan section 22 of the engine 20 is designed for a particular flight condition - typically cruise at about 0.8 Mach and about 35,000 feet.
  • 'TSFC' Thrust Specific Fuel Consumption
  • Fan pressure ratio is the pressure ratio across the fan blade alone, without a Fan Exit Guide Vane (“FEGV”) system.
  • the low fan pressure ratio as disclosed herein according to one non- limiting embodiment is less than about 1.45.
  • “Low corrected fan tip speed” is the actual fan tip speed in ft/sec divided by an industry standard temperature correction of [(Tram deg R) / 518.7) ⁇ 0.5].
  • the "Low corrected fan tip speed” as disclosed herein according to one non- limiting embodiment is less than about 1150 ft / second.
  • FIG. 1 An example geared architecture 48 for the engine 20 is shown in Figure 2.
  • the engine static structure 36 supports the inner and outer shafts 40, 50 for rotation about the axis A.
  • the outer shaft 50 supports the high pressure compressor section 52 and the high pressure turbine section 54, which is arranged upstream from the mid turbine frame 59.
  • the inner shaft 40 is coupled to the geared architecture 48, which is an epicyclic gear train 60 configured in a differential arrangement.
  • the gear train 60 includes planetary gears 64 supported by a carrier 62, which is connected to the inner shaft 40 that supports the low pressure turbine 46.
  • a sun gear 66 is centrally arranged relative to and intermeshes with the planetary gears 64.
  • a ring gear 70 circumscribes and intermeshes with the planetary gears 64.
  • a fan shaft 72 which is connected to the fan 42, is rotationally fixed relative to the ring gear 70.
  • the low pressure compressor 44 is supported by a low pressure compressor rotor 68, which is connected to the sun gear 66 in the example.
  • the carrier 62 is rotationally driven by the low pressure turbine 46 through the inner shaft 40.
  • the planetary gears 64 provide the differential input to the fan shaft 72 and low pressure compressor rotor 68 based upon the geometry ratio, which is discussed in detail in connection with Figures 9 A- 10.
  • FIG. 3 Another example geared architecture 148 for the engine 120 is shown in Figure 3.
  • the engine static structure 136 supports the inner and outer shafts 140, 150 for rotation about the axis A.
  • the outer shaft 150 supports the high pressure compressor section 152 and the high pressure turbine section 154, which is arranged upstream from the mid turbine frame 159.
  • the inner shaft 140 is coupled to the geared architecture 148, which is an epicyclic gear train 160 configured in a differential arrangement.
  • the gear train 160 includes planetary gears 164 supported by a carrier 162, which is connected to the inner shaft 140 that supports the low pressure turbine 146.
  • a sun gear 166 is centrally arranged relative to and intermeshes with the planetary gears 164.
  • a ring gear 170 circumscribes and intermeshes with the planetary gears 164.
  • a fan shaft 172 which is connected to the fan 142, is rotationally fixed relative to the ring gear 170.
  • the low pressure compressor 144 is supported by a low pressure compressor rotor 168, which is connected to the sun gear 166 in the example.
  • the carrier 162 is rotationally driven by the low pressure turbine 146 through the inner shaft 140.
  • the planetary gears 164 provide the differential input to the fan shaft 172 and low pressure compressor rotor 168 based upon the geometry ratio.
  • the geared architecture 148 includes an additional speed change device 74 interconnecting the inner shaft 140 and the gear train 160. Higher low pressure turbine section rotational speeds are attainable with the additional speed change device 74, enabling the use of fewer turbine stages in the low pressure turbine section.
  • the speed change device 74 may be a geared arrangement and/or a hydraulic arrangement for reducing the rotational speed from the low pressure turbine section 146 to the fan 142 and low pressure compressor section 144.
  • FIG. 4 Another example geared architecture 248 for the engine 220 is shown in Figure 4.
  • the engine static structure 236 supports the inner and outer shafts 240, 250 for rotation about the axis A.
  • the outer shaft 250 supports the high pressure compressor section 252 and the high pressure turbine section 254, which is arranged upstream from the mid turbine frame 259.
  • the inner shaft 240 is coupled to the geared architecture 248, which is an epicyclic gear train 260 configured in a differential arrangement.
  • the gear train 260 includes planetary gears 264 supported by a carrier 262, which is connected to the inner shaft 240 that supports the low pressure turbine 246.
  • a sun gear 266 is centrally arranged relative to and intermeshes with the planetary gears 264.
  • a ring gear 270 circumscribes and intermeshes with the planetary gears 264.
  • a fan shaft 272 which is connected to the fan 242, is rotationally fixed relative to the ring gear 270.
  • the low pressure compressor 244 is supported by a low pressure compressor rotor 268, which is connected to the sun gear 266 in the example.
  • the carrier 262 is rotationally driven by the low pressure turbine 246 through the inner shaft 240.
  • the planetary gears 264 provide the differential input to the fan shaft 272 and low pressure compressor rotor 268 based upon the geometry ratio.
  • the geared architecture 248 includes an additional speed change device 274 interconnecting the inner shaft 240 and the gear train 260.
  • An inducer 76 is fixed for rotation relative to the ring gear 270.
  • the inducer 76 is arranged in the core flow path C to provide some initial compression to the air before entering the low pressure compressor section 244.
  • the inducer 76 rotates at the same rotational speed as the fan 242 and provides some additional thrust, which is useful in hot weather, for example, where engine thrust is reduced.
  • FIG. 5 Another example geared architecture 348 for the engine 320 is shown in Figure 5.
  • the engine static structure 336 supports the inner and outer shafts 340, 350 for rotation about the axis A.
  • the outer shaft 350 supports the high pressure compressor section 352 and the high pressure turbine section 354, which is arranged upstream from the mid turbine frame 359.
  • the inner shaft 340 is coupled to the geared architecture 348, which is an epicyclic gear train 360 configured in a differential arrangement.
  • the gear train 360 includes planetary gears 364 supported by a carrier 362, which is connected to the inner shaft 340 that supports the low pressure turbine 346.
  • a sun gear 366 is centrally arranged relative to and intermeshes with the planetary gears 364.
  • a ring gear 370 circumscribes and intermeshes with the planetary gears 364.
  • a fan shaft 372 is connected to the fan 342.
  • the low pressure compressor 344 is supported by a low pressure compressor rotor 368, which is rotationally fixed relative to the ring gear 370 in the example.
  • the carrier 362 is rotationally driven by the low pressure turbine 346 through the inner shaft 340.
  • the planetary gears 364 provide the differential input to the fan shaft 372 and low pressure compressor rotor 368 based upon the geometry ratio.
  • the geared architecture 348 includes an additional speed change device 374 interconnecting the inner shaft 340 and the gear train 360. The speed change device 374 receives rotational input from the sun gear 366 and couples the fan shaft 372 to the gear train 360, which enables slower fan speeds.
  • FIG. 6 Another example geared architecture 448 for the engine 420 is shown in Figure 6.
  • the engine static structure 436 supports the inner and outer shafts 440, 450 for rotation about the axis A.
  • the outer shaft 450 supports the high pressure compressor section 452 and the high pressure turbine section 454, which is arranged upstream from the mid turbine frame 459.
  • the inner shaft 440 is coupled to the geared architecture 448, which is an epicyclic gear train 460 configured in a differential arrangement.
  • the gear train 460 includes planetary gears 464 supported by a carrier 462, which is connected to the inner shaft 440 that supports the low pressure turbine 446.
  • a sun gear 466 is centrally arranged relative to and intermeshes with the planetary gears 464.
  • a ring gear 470 circumscribes and intermeshes with the planetary gears 464.
  • a fan shaft 472 is connected to the fan 442.
  • the low pressure compressor 444 is supported by a low pressure compressor rotor 468, which is rotationally fixed relative to the ring gear 470 in the example.
  • the carrier 462 is rotationally driven by the low pressure compressor 446 through the inner shaft 440.
  • the planetary gears 464 provide the differential input to the fan shaft 472 and low pressure compressor rotor 468 based upon the geometry ratio.
  • the geared architecture 448 includes an additional speed change device 474 interconnecting the inner shaft 440 and the gear train 460. The speed change device 474 receives rotational input from the sun gear 466 and couples the fan shaft 472 to the gear train 460, which enables slower fan speeds.
  • the inducer 476 is fixed for rotation relative to the fan shaft 472.
  • the inducer 476 is arranged in the core flow path C to provide some initial compression to the air before entering the low pressure compressor section 444.
  • the inducer 476 rotates at the same rotational speed as the fan 442.
  • FIG. 7 Another example geared architecture 548 for the engine 520 is shown in Figure 7.
  • the engine static structure 536 supports the inner and outer shafts 540, 550 for rotation about the axis A.
  • the outer shaft 550 supports the high pressure compressor section 552 and the high pressure turbine section 554, which is arranged upstream from the mid turbine frame 559.
  • the inner shaft 540 is coupled to the geared architecture 548, which is an epicyclic gear train 560 configured in a differential arrangement.
  • the gear train 560 includes planetary gears 564 supported by a carrier 562, which is connected to the inner shaft 540 that supports the low pressure turbine 546.
  • a sun gear 566 is centrally arranged relative to and intermeshes with the planetary gears 564.
  • a ring gear 570 circumscribes and intermeshes with the planetary gears 564.
  • a fan shaft 572 is connected to the fan 542.
  • the low pressure compressor 544 is supported by a low pressure compressor rotor 568, which is rotationally fixed relative to the ring gear 570 in the example.
  • the carrier 562 is rotationally driven by the low pressure turbine 546 through the inner shaft 540.
  • the planetary gears 564 provide the differential input to the fan shaft 572 and low pressure compressor rotor 568 based upon the geometry ratio.
  • the geared architecture 548 includes an additional speed change device 574 interconnecting the inner shaft 540 and the gear train 560. The speed change device 574 receives rotational input from the sun gear 566 and couples the fan shaft 572 to the gear train 560, which enables slower fan speeds.
  • the inducer 576 is fixed for rotation relative to the fan shaft 572.
  • the inducer 576 is arranged in the core flow path C to provide some initial compression to the air before entering the low pressure compressor section 544.
  • the sun gear 566 rotates at the same speed as one of the fan shaft 572 and the inducer 576, and the other of the fan shaft 572 and the inducer 576 rotate at a different speed than the sun gear 566.
  • the inducer 576, sun gear 566 and fan shaft 572 rotate at different rotational speeds than one another through the speed change device 574, which is another epicyclic gear train, for example.
  • FIG. 8 Another example geared architecture 648 for the engine 620 is shown in Figure 8.
  • the engine static structure 636 supports the inner and outer shafts 640, 650 for rotation about the axis A.
  • the outer shaft 650 supports the high pressure compressor section 652 and the high pressure turbine section 654, which is arranged upstream from the mid turbine frame 659.
  • the inner shaft 640 is coupled to the geared architecture 648, which is an epicyclic gear train 660 configured in a differential arrangement.
  • the gear train 660 includes planetary gears 664 supported by a carrier 662, which is connected to the inner shaft 640 that supports the low pressure turbine 646.
  • a sun gear 666 is centrally arranged relative to and intermeshes with the planetary gears 664.
  • a ring gear 670 circumscribes and intermeshes with the planetary gears 664.
  • a fan shaft 672 is connected to the fan 642.
  • the low pressure compressor 644 is supported by a low pressure compressor rotor 668, which is rotationally fixed relative to the ring gear 670 in the example.
  • the carrier 662 is rotationally driven by the low pressure turbine 646 through the inner shaft 640.
  • the planetary gears 664 provide the differential input to the fan shaft 672 and low pressure compressor rotor 668 based upon the geometry ratio.
  • the geared architecture 648 includes an additional speed change device 674 interconnecting the inner shaft 640 and the gear train 660. The speed change device 674 receives rotational input from the sun gear 666 and couples the fan shaft 672 to the gear train 660, which enables slower fan speeds.
  • the inducer 676 is arranged in the core flow path C to provide some initial compression to the air before entering the low pressure compressor section 644.
  • the inducer 676 is fixed to the sun gear 666 for rotation at the same rotational speed.
  • the relative rotational directions are shown for each of the fan, low pressure compressor section, high pressure compressor section, high pressure turbine section, low pressure turbine section and inducer.
  • the geared architectures may be configured in a manner to provide the desired rotational direction for a given engine design.
  • the example geared architectures enable large fan diameters relative to turbine diameters, moderate low pressure turbine to fan speed ratios, moderate low pressure compressor to low pressure turbine speed ratios, high low pressure compressor to fan speed ratios and compact turbine section volumes.
  • the low pressure turbine section may include between three and six stages, for example.
  • Xcarrier is the nomograph distance of the planetary rotational axis from the sun gear axis
  • Xring is the nomograph radius of the ring gear
  • GR is the geometry ratio.
  • ' ⁇ " 1?r 0.75.
  • the epicyclic gear train 760 includes a sun gear 766, planetary 764, carrier 762 and ring gear 770 that are sized to provide a geometry ratio of 3.0.
  • the epicyclic gear train 860 includes a sun gear 866, planetary 864, carrier 862 and ring gear 870 that are sized to provide a geometry ratio of 2.0.
  • the epicyclic gear train 960 includes a sun gear 966, planetary 964, carrier 962 and ring gear 970 that are sized to provide a geometry ratio of 1.5. In the examples, the ring gear radius remains constant.
  • Figure 10 graphically depicts effects of the geometry ratio on the rotational speeds and directions of the sun and ring gears and the carrier.
  • the upper, lighter shaded bars relate to Figure 9A-9C.
  • the sun gear would be driven at 15,000 RPM and the ring gear would be driven at 8,333 RPM for a geometry ratio of 3.0.

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Retarders (AREA)

Abstract

A gas turbine engine includes first and second shafts rotatable about a common axis. A first turbine section is supported on the first shaft. Second compressor and turbine sections are supported on the second shaft. The gas turbine engine includes a fan. A first compressor section is arranged in an axial flow relationship with the second compressor and the first and second turbines. A geared architecture operatively connects the first shaft and the fan. An inducer operative couples to the gear train.

Description

GEARED ARCHITECTURE WITH INDUCER FOR
GAS TURBINE ENGINE
[0001] This application claims priority to U.S. Patent Application Serial No. 13/437,395 which was filed on April 2, 2012.
BACKGROUND
[0002] This disclosure relates to a geared architecture for a gas turbine engine.
[0003] One type of geared turbofan engine includes a two-spool arrangement in which a low spool, which supports a low pressure turbine section, is coupled to a fan via a planetary gear train. A high pressure spool supports a high pressure turbine section. Low and high pressure compressor sections are respectively supported by the low and high spools.
[0004] The planetary gear train includes a planetary gear set surrounding and intermeshing with a centrally located sun gear that is connected to the low spool. A ring gear circumscribes and intermeshes with the planetary gears. A fan shaft supports the fan. The fan shaft is connected to either the planetary gears or the ring gear, and the other of the planetary gears and ring gear is grounded to the engine static structure. This type of planetary gear arrangement can limit the design speeds of and configuration of stages in the low and high pressure turbine sections.
SUMMARY
[0005] In one exemplary embodiment, a gas turbine engine includes first and second shafts rotatable about a common axis. A first turbine section is supported on the first shaft. Second compressor and turbine sections are supported on the second shaft. The gas turbine engine includes a fan. A first compressor section is arranged in an axial flow relationship with the second compressor and the first and second turbines. A geared architecture operatively connects the first shaft and the fan. An inducer operative couples to the gear train.
[0006] In a further embodiment of any of the above, the gas turbine engine includes a bypass flow path and a core flow path. The first and second compressor and turbine sections are arranged in the core flow path, and the fan extends into the bypass flow path. The inducer is arranged in the core flow path outside of the bypass flow path and upstream from the first compressor section. [0007] In a further embodiment of any of the above, first and second shafts respectively provide low and high spools. The first compressor and turbine sections are low pressure compressor and turbine sections. The second compressor and turbine sections are high pressure compressor and turbine sections.
[0008] In a further embodiment of any of the above, the geared architecture includes first and second gear trains. The first gear train is an epicyclic gear train, and the second gear train is configured to provide a speed reduction.
[0009] In a further embodiment of any of the above, the inducer is coupled to the first gear train. The epicyclic gear train is a differential gear train that includes a sun gear. Planetary gears are arranged about and intermesh with the sun gear. A ring gear circumscribes and intermeshes with the planetary gears.
[0010] In a further embodiment of any of the above, the inducer is rotationally fixed relative to the ring gear.
[0011] In a further embodiment of any of the above, the inducer is rotationally fixed relative to the star gear.
[0012] In a further embodiment of any of the above, the inducer is coupled to the second gear train.
[0013] In a further embodiment of any of the above, the inducer is rotationally fixed relative to the fan.
[0014] In a further embodiment of any of the above, the inducer is configured to rotate at a different rotational speed than the first compressor section.
[0015] In a further embodiment of any of the above, the inducer is configured to rotate at a different rotational speed than the fan.
[0016] In a further embodiment of any of the above, the inducer is configured to rotate at a different rotational speed than the fan.
[0017] In one exemplary embodiment, a gas turbine engine includes first and second shafts rotatable about a common axis. A first turbine section is supported on the first shaft. Second compressor and turbine sections are supported on the second shaft. The gas turbine engine includes a fan. A first compressor section is arranged in an axial flow relationship with the second compressor and the first and second turbines. A geared architecture operatively connects the first shaft and the fan. An inducer is operatively coupled to the gear train. The gas turbine engine includes a bypass flow path and a core flow path. The first and second compressor and turbine sections are arranged in the core flow path, and the fan extends into the bypass flow path. The inducer is arranged in the core flow path outside of the bypass flow path and upstream from the first compressor section. First and second shafts respectively provide low and high spools. The first compressor and turbine sections are low pressure compressor and turbine sections, and the second compressor and turbine sections are high pressure compressor and turbine sections. The geared architecture includes first and second gear trains. The first gear train is an epicyclic gear train, and the second gear train is configured to provide a speed reduction.
[0018] In a further embodiment of any of the above, the inducer is coupled to the first gear train. The epicyclic gear train is a differential gear train that includes a sun gear. Planetary gears are arranged about and intermesh with the sun gear. A ring gear circumscribes and intermeshes with the planetary gears.
[0019] In a further embodiment of any of the above, the inducer is rotationally fixed relative to the ring gear.
[0020] In a further embodiment of any of the above, the inducer is rotationally fixed relative to the star gear.
[0021] In a further embodiment of any of the above, the inducer is coupled to the second gear train.
[0022] In a further embodiment of any of the above, the inducer is rotationally fixed relative to the fan.
[0023] In a further embodiment of any of the above, the inducer is configured to rotate at a different rotational speed than the first compressor section.
[0024] In a further embodiment of any of the above, the inducer is configured to rotate at a different rotational speed than the fan.
[0025] In a further embodiment of any of the above, the inducer is configured to rotate at a different rotational speed than the fan. BRIEF DESCRIPTION OF THE DRAWINGS
[0026] The disclosure can be further understood by reference to the following detailed description when considered in connection with the accompanying drawings wherein:
[0027] Figure 1 schematically illustrates a gas turbine engine embodiment.
[0028] Figure 2 is a schematic view of a geared architecture embodiment for the engine shown in Figure 1.
[0029] Figure 3 is a schematic view of another geared architecture embodiment.
[0030] Figure 4 is a schematic view of a geared architecture embodiment with an inducer.
[0031] Figure 5 is a schematic view of yet another geared architecture embodiment.
[0032] Figure 6 is a schematic view of another geared architecture embodiment with an inducer.
[0033] Figure 7 is a schematic view of yet another geared architecture embodiment with an inducer.
[0034] Figure 8 is a schematic view of still another geared architecture embodiment with an inducer.
[0035] Figure 9A is a schematic view of an epicyclic gear train having a first example geometry ratio.
[0036] Figure 9B is a schematic view of an epicyclic gear train having a second example geometry ratio.
[0037] Figure 9C is a schematic view of an epicyclic gear train having a third example geometry ratio.
[0038] Figure 10 is a nomograph depicting the interrelationship of speeds of epicyclic gear train components for a given geometry ratio.
[0039] Figure 11A is a schematic view of an epicyclic gear train having the first geometry ratio with a carrier rotating in the opposite direction to that shown in Figure 9A.
[0040] Figure 11B is a schematic view of an epicyclic gear train having the second geometry ratio with a carrier rotating in the opposite direction to that shown in Figure 9B. [0041] Figure 11C is a schematic view of an epicyclic gear train having the third geometry ratio with a carrier rotating in the opposite direction to that shown in Figure 9C.
DETAILED DESCRIPTION
[0042] Figure 1 schematically illustrates a gas turbine engine 20. The gas turbine engine 20 is disclosed herein as a two-spool turbofan that generally incorporates a fan section 22, a compressor section 24, a combustor section 26 and a turbine section 28. Alternative engines might include an augmentor section (not shown) among other systems or features. The fan section 22 drives air along a bypass flowpath B while the compressor section 24 drives air along a core flowpath C for compression and communication into the combustor section 26 then expansion through the turbine section 28. Although depicted as a turbofan gas turbine engine in the disclosed non-limiting embodiment, it should be understood that the concepts described herein are not limited to use with turbofans as the teachings may be applied to other types of turbine engines including three-spool architectures.
[0043] The engine 20 generally includes a low speed spool 30 and a high speed spool 32 mounted for rotation about an engine central longitudinal axis A relative to an engine static structure 36 via several bearing systems 38. It should be understood that various bearing systems 38 at various locations may alternatively or additionally be provided.
[0044] The low speed spool 30 generally includes an inner shaft 40 that interconnects a fan 42, a low pressure (or first) compressor section 44 and a low pressure (or first) turbine section 46. The inner shaft 40 is connected to the fan 42 through a geared architecture 48 to drive the fan 42 at a lower speed than the low speed spool 30. The high speed spool 32 includes an outer shaft 50 that interconnects a high pressure (or second) compressor section 52 and high pressure (or second) turbine section 54. A combustor 56 is arranged between the high pressure compressor 52 and the high pressure turbine 54. A mid- turbine frame 57 of the engine static structure 36 is arranged generally between the high pressure turbine 54 and the low pressure turbine 46. The mid-turbine frame 57 supports one or more bearing systems 38 in the turbine section 28. The inner shaft 40 and the outer shaft 50 are concentric and rotate via bearing systems 38 about the engine central longitudinal axis A, which is collinear with their longitudinal axes. As used herein, a "high pressure" compressor or turbine experiences a higher pressure than a corresponding "low pressure" compressor or turbine.
[0045] The core airflow C is compressed by the low pressure compressor 44 then the high pressure compressor 52, mixed and burned with fuel in the combustor 56, then expanded over the high pressure turbine 54 and low pressure turbine 46. The mid-turbine frame 57 includes airfoils 59 which are in the core airflow path. The turbines 46, 54 rotationally drive the respective low speed spool 30 and high speed spool 32 in response to the expansion.
[0046] The engine 20 in one example is a high-bypass geared aircraft engine. In a further example, the engine 20 bypass ratio is greater than about six (6), with an example embodiment being greater than ten (10), the geared architecture 48 is an epicyclic gear train, such as a star gear system or other gear system, with a gear reduction ratio of greater than about 2.3 and the low pressure turbine 46 has a pressure ratio that is greater than about 5. In one disclosed embodiment, the engine 20 bypass ratio is greater than about ten (10: 1), the fan diameter is significantly larger than that of the low pressure compressor 44, and the low pressure turbine 46 has a pressure ratio that is greater than about 5: 1. Low pressure turbine 46 pressure ratio is pressure measured prior to inlet of low pressure turbine 46 as related to the pressure at the outlet of the low pressure turbine 46 prior to an exhaust nozzle. It should be understood, however, that the above parameters are only exemplary of one embodiment of a geared architecture engine and that the present invention is applicable to other gas turbine engines including direct drive turbofans.
[0047] A significant amount of thrust is provided by the bypass flow B due to the high bypass ratio. The fan section 22 of the engine 20 is designed for a particular flight condition - typically cruise at about 0.8 Mach and about 35,000 feet. The flight condition of
0.8 Mach and 35,000 ft, with the engine at its best fuel consumption - also known as "bucket cruise Thrust Specific Fuel Consumption ('TSFC')" - is the industry standard parameter of lbm of fuel being burned per hour divided by lbf of thrust the engine produces at that minimum point. "Fan pressure ratio" is the pressure ratio across the fan blade alone, without a Fan Exit Guide Vane ("FEGV") system. The low fan pressure ratio as disclosed herein according to one non- limiting embodiment is less than about 1.45. "Low corrected fan tip speed" is the actual fan tip speed in ft/sec divided by an industry standard temperature correction of [(Tram deg R) / 518.7)Λ0.5]. The "Low corrected fan tip speed" as disclosed herein according to one non- limiting embodiment is less than about 1150 ft / second.
[0048] An example geared architecture 48 for the engine 20 is shown in Figure 2. Generally, the engine static structure 36 supports the inner and outer shafts 40, 50 for rotation about the axis A. The outer shaft 50 supports the high pressure compressor section 52 and the high pressure turbine section 54, which is arranged upstream from the mid turbine frame 59.
[0049] The inner shaft 40 is coupled to the geared architecture 48, which is an epicyclic gear train 60 configured in a differential arrangement. The gear train 60 includes planetary gears 64 supported by a carrier 62, which is connected to the inner shaft 40 that supports the low pressure turbine 46. A sun gear 66 is centrally arranged relative to and intermeshes with the planetary gears 64. A ring gear 70 circumscribes and intermeshes with the planetary gears 64. In the example, a fan shaft 72, which is connected to the fan 42, is rotationally fixed relative to the ring gear 70. The low pressure compressor 44 is supported by a low pressure compressor rotor 68, which is connected to the sun gear 66 in the example.
[0050] The carrier 62 is rotationally driven by the low pressure turbine 46 through the inner shaft 40. The planetary gears 64 provide the differential input to the fan shaft 72 and low pressure compressor rotor 68 based upon the geometry ratio, which is discussed in detail in connection with Figures 9 A- 10.
[0051] Another example geared architecture 148 for the engine 120 is shown in Figure 3. The engine static structure 136 supports the inner and outer shafts 140, 150 for rotation about the axis A. The outer shaft 150 supports the high pressure compressor section 152 and the high pressure turbine section 154, which is arranged upstream from the mid turbine frame 159.
[0052] The inner shaft 140 is coupled to the geared architecture 148, which is an epicyclic gear train 160 configured in a differential arrangement. The gear train 160 includes planetary gears 164 supported by a carrier 162, which is connected to the inner shaft 140 that supports the low pressure turbine 146. A sun gear 166 is centrally arranged relative to and intermeshes with the planetary gears 164. A ring gear 170 circumscribes and intermeshes with the planetary gears 164. In the example, a fan shaft 172, which is connected to the fan 142, is rotationally fixed relative to the ring gear 170. The low pressure compressor 144 is supported by a low pressure compressor rotor 168, which is connected to the sun gear 166 in the example.
[0053] The carrier 162 is rotationally driven by the low pressure turbine 146 through the inner shaft 140. The planetary gears 164 provide the differential input to the fan shaft 172 and low pressure compressor rotor 168 based upon the geometry ratio. The geared architecture 148 includes an additional speed change device 74 interconnecting the inner shaft 140 and the gear train 160. Higher low pressure turbine section rotational speeds are attainable with the additional speed change device 74, enabling the use of fewer turbine stages in the low pressure turbine section. The speed change device 74 may be a geared arrangement and/or a hydraulic arrangement for reducing the rotational speed from the low pressure turbine section 146 to the fan 142 and low pressure compressor section 144.
[0054] Another example geared architecture 248 for the engine 220 is shown in Figure 4. The engine static structure 236 supports the inner and outer shafts 240, 250 for rotation about the axis A. The outer shaft 250 supports the high pressure compressor section 252 and the high pressure turbine section 254, which is arranged upstream from the mid turbine frame 259.
[0055] The inner shaft 240 is coupled to the geared architecture 248, which is an epicyclic gear train 260 configured in a differential arrangement. The gear train 260 includes planetary gears 264 supported by a carrier 262, which is connected to the inner shaft 240 that supports the low pressure turbine 246. A sun gear 266 is centrally arranged relative to and intermeshes with the planetary gears 264. A ring gear 270 circumscribes and intermeshes with the planetary gears 264. In the example, a fan shaft 272, which is connected to the fan 242, is rotationally fixed relative to the ring gear 270. The low pressure compressor 244 is supported by a low pressure compressor rotor 268, which is connected to the sun gear 266 in the example.
[0056] The carrier 262 is rotationally driven by the low pressure turbine 246 through the inner shaft 240. The planetary gears 264 provide the differential input to the fan shaft 272 and low pressure compressor rotor 268 based upon the geometry ratio. The geared architecture 248 includes an additional speed change device 274 interconnecting the inner shaft 240 and the gear train 260. [0057] An inducer 76 is fixed for rotation relative to the ring gear 270. The inducer 76 is arranged in the core flow path C to provide some initial compression to the air before entering the low pressure compressor section 244. The inducer 76 rotates at the same rotational speed as the fan 242 and provides some additional thrust, which is useful in hot weather, for example, where engine thrust is reduced.
[0058] Another example geared architecture 348 for the engine 320 is shown in Figure 5. The engine static structure 336 supports the inner and outer shafts 340, 350 for rotation about the axis A. The outer shaft 350 supports the high pressure compressor section 352 and the high pressure turbine section 354, which is arranged upstream from the mid turbine frame 359.
[0059] The inner shaft 340 is coupled to the geared architecture 348, which is an epicyclic gear train 360 configured in a differential arrangement. The gear train 360 includes planetary gears 364 supported by a carrier 362, which is connected to the inner shaft 340 that supports the low pressure turbine 346. A sun gear 366 is centrally arranged relative to and intermeshes with the planetary gears 364. A ring gear 370 circumscribes and intermeshes with the planetary gears 364. In the example, a fan shaft 372 is connected to the fan 342. The low pressure compressor 344 is supported by a low pressure compressor rotor 368, which is rotationally fixed relative to the ring gear 370 in the example.
[0060] The carrier 362 is rotationally driven by the low pressure turbine 346 through the inner shaft 340. The planetary gears 364 provide the differential input to the fan shaft 372 and low pressure compressor rotor 368 based upon the geometry ratio. The geared architecture 348 includes an additional speed change device 374 interconnecting the inner shaft 340 and the gear train 360. The speed change device 374 receives rotational input from the sun gear 366 and couples the fan shaft 372 to the gear train 360, which enables slower fan speeds.
[0061] Another example geared architecture 448 for the engine 420 is shown in Figure 6. The engine static structure 436 supports the inner and outer shafts 440, 450 for rotation about the axis A. The outer shaft 450 supports the high pressure compressor section 452 and the high pressure turbine section 454, which is arranged upstream from the mid turbine frame 459. [0062] The inner shaft 440 is coupled to the geared architecture 448, which is an epicyclic gear train 460 configured in a differential arrangement. The gear train 460 includes planetary gears 464 supported by a carrier 462, which is connected to the inner shaft 440 that supports the low pressure turbine 446. A sun gear 466 is centrally arranged relative to and intermeshes with the planetary gears 464. A ring gear 470 circumscribes and intermeshes with the planetary gears 464. In the example, a fan shaft 472 is connected to the fan 442. The low pressure compressor 444 is supported by a low pressure compressor rotor 468, which is rotationally fixed relative to the ring gear 470 in the example.
[0063] The carrier 462 is rotationally driven by the low pressure compressor 446 through the inner shaft 440. The planetary gears 464 provide the differential input to the fan shaft 472 and low pressure compressor rotor 468 based upon the geometry ratio. The geared architecture 448 includes an additional speed change device 474 interconnecting the inner shaft 440 and the gear train 460. The speed change device 474 receives rotational input from the sun gear 466 and couples the fan shaft 472 to the gear train 460, which enables slower fan speeds.
[0064] The inducer 476 is fixed for rotation relative to the fan shaft 472. The inducer 476 is arranged in the core flow path C to provide some initial compression to the air before entering the low pressure compressor section 444. The inducer 476 rotates at the same rotational speed as the fan 442.
[0065] Another example geared architecture 548 for the engine 520 is shown in Figure 7. The engine static structure 536 supports the inner and outer shafts 540, 550 for rotation about the axis A. The outer shaft 550 supports the high pressure compressor section 552 and the high pressure turbine section 554, which is arranged upstream from the mid turbine frame 559.
[0066] The inner shaft 540 is coupled to the geared architecture 548, which is an epicyclic gear train 560 configured in a differential arrangement. The gear train 560 includes planetary gears 564 supported by a carrier 562, which is connected to the inner shaft 540 that supports the low pressure turbine 546. A sun gear 566 is centrally arranged relative to and intermeshes with the planetary gears 564. A ring gear 570 circumscribes and intermeshes with the planetary gears 564. In the example, a fan shaft 572 is connected to the fan 542. The low pressure compressor 544 is supported by a low pressure compressor rotor 568, which is rotationally fixed relative to the ring gear 570 in the example.
[0067] The carrier 562 is rotationally driven by the low pressure turbine 546 through the inner shaft 540. The planetary gears 564 provide the differential input to the fan shaft 572 and low pressure compressor rotor 568 based upon the geometry ratio. The geared architecture 548 includes an additional speed change device 574 interconnecting the inner shaft 540 and the gear train 560. The speed change device 574 receives rotational input from the sun gear 566 and couples the fan shaft 572 to the gear train 560, which enables slower fan speeds.
[0068] The inducer 576 is fixed for rotation relative to the fan shaft 572. The inducer 576 is arranged in the core flow path C to provide some initial compression to the air before entering the low pressure compressor section 544. In one example, the sun gear 566 rotates at the same speed as one of the fan shaft 572 and the inducer 576, and the other of the fan shaft 572 and the inducer 576 rotate at a different speed than the sun gear 566. In another example, the inducer 576, sun gear 566 and fan shaft 572 rotate at different rotational speeds than one another through the speed change device 574, which is another epicyclic gear train, for example.
[0069] Another example geared architecture 648 for the engine 620 is shown in Figure 8. The engine static structure 636 supports the inner and outer shafts 640, 650 for rotation about the axis A. The outer shaft 650 supports the high pressure compressor section 652 and the high pressure turbine section 654, which is arranged upstream from the mid turbine frame 659.
[0070] The inner shaft 640 is coupled to the geared architecture 648, which is an epicyclic gear train 660 configured in a differential arrangement. The gear train 660 includes planetary gears 664 supported by a carrier 662, which is connected to the inner shaft 640 that supports the low pressure turbine 646. A sun gear 666 is centrally arranged relative to and intermeshes with the planetary gears 664. A ring gear 670 circumscribes and intermeshes with the planetary gears 664. In the example, a fan shaft 672 is connected to the fan 642. The low pressure compressor 644 is supported by a low pressure compressor rotor 668, which is rotationally fixed relative to the ring gear 670 in the example. [0071] The carrier 662 is rotationally driven by the low pressure turbine 646 through the inner shaft 640. The planetary gears 664 provide the differential input to the fan shaft 672 and low pressure compressor rotor 668 based upon the geometry ratio. The geared architecture 648 includes an additional speed change device 674 interconnecting the inner shaft 640 and the gear train 660. The speed change device 674 receives rotational input from the sun gear 666 and couples the fan shaft 672 to the gear train 660, which enables slower fan speeds.
[0072] The inducer 676 is arranged in the core flow path C to provide some initial compression to the air before entering the low pressure compressor section 644. The inducer 676 is fixed to the sun gear 666 for rotation at the same rotational speed.
[0073] In the arrangements shown in Figures 2-8, the relative rotational directions are shown for each of the fan, low pressure compressor section, high pressure compressor section, high pressure turbine section, low pressure turbine section and inducer. The geared architectures may be configured in a manner to provide the desired rotational direction for a given engine design.
[0074] The example geared architectures enable large fan diameters relative to turbine diameters, moderate low pressure turbine to fan speed ratios, moderate low pressure compressor to low pressure turbine speed ratios, high low pressure compressor to fan speed ratios and compact turbine section volumes. The low pressure turbine section may include between three and six stages, for example.
[0075] The rotational speeds of the sun gear, ring gear and carrier are determined by the geometry ratio of the differential gear train. The interrelationship of these components can be expressed using the following equation:
garr»r _ wnere (Equation 1)
Xcarrier is the nomograph distance of the planetary rotational axis from the sun gear axis,
Xring is the nomograph radius of the ring gear, and
GR is the geometry ratio. Thus, for a geometry ratio of 3.0, ' ^ " 1?r = 0.75.
[0076] The relative sizes amongst the sun gear, planetary gears and ring gear for several different geometry ratios are schematically depicted in Figures 9A-9C. Referring to Figure 9A, the epicyclic gear train 760 includes a sun gear 766, planetary 764, carrier 762 and ring gear 770 that are sized to provide a geometry ratio of 3.0. Referring to Figure 9B, the epicyclic gear train 860 includes a sun gear 866, planetary 864, carrier 862 and ring gear 870 that are sized to provide a geometry ratio of 2.0. Referring to Figure 9C, the epicyclic gear train 960 includes a sun gear 966, planetary 964, carrier 962 and ring gear 970 that are sized to provide a geometry ratio of 1.5. In the examples, the ring gear radius remains constant.
[0077] Figure 10 graphically depicts effects of the geometry ratio on the rotational speeds and directions of the sun and ring gears and the carrier. The upper, lighter shaded bars relate to Figure 9A-9C. Assuming a rotational input from the low pressure turbine to the carrier of 10,000 RPM, the sun gear would be driven at 15,000 RPM and the ring gear would be driven at 8,333 RPM for a geometry ratio of 3.0. In an arrangement in which the fan is coupled to the ring gear and the sun gear is coupled to the low pressure compressor, like the arrangement shown in Figure 2, the following speed ratios would be provided: LPT:fan = 1.2, LPC:LPT = 1.5, and LPC:fan = 1.8.
[0078] The lower, darker shaded bars relate to Figures 11 A-l 1C. The carrier and ring gear rotate in the opposite direction than depicted in Figure 9A-9C.
[0079] Although an example embodiment has been disclosed, a worker of ordinary skill in this art would recognize that certain modifications would come within the scope of the claims. For that reason, the following claims should be studied to determine their true scope and content.

Claims

CLAIMS What is claimed is:
1. A gas turbine engine comprising:
first and second shafts rotatable about a common axis;
a first turbine section supported on the first shaft;
second compressor and turbine sections supported on the second shaft;
a fan;
a first compressor section arranged in an axial flow relationship with the second compressor and the first and second turbines;
a geared architecture operatively connecting the first shaft and the fan; and an inducer operative coupled to the gear train.
2. The gas turbine engine according to claim 1, comprising a bypass flow path and a core flow path, the first and second compressor and turbine sections arranged in the core flow path, and the fan extending into the bypass flow path, the inducer arranged in the core flow path outside of the bypass flow path and upstream from the first compressor section.
3. The gas turbine engine according to claim 2, wherein first and second shafts respectively provide low and high spools, and the first compressor and turbine sections are low pressure compressor and turbine sections, and the second compressor and turbine sections are high pressure compressor and turbine sections.
4. The gas turbine engine according to claim 1, wherein the geared architecture includes first and second gear trains, the first gear train an epicyclic gear train, and the second gear train configured to provide a speed reduction.
5. The gas turbine engine according to claim 4, wherein the inducer is coupled to the first gear train, the epicyclic gear train is a differential gear train that includes a sun gear, planetary gears arranged about and intermeshing with the sun gear, and a ring gear circumscribing and intermeshing with the planetary gears.
6. The gas turbine engine according to claim 5, wherein the inducer is rotationally fixed relative to the ring gear.
7. The gas turbine engine according to claim 5, wherein the inducer is rotationally fixed relative to the star gear.
8. The gas turbine engine according to claim 4, wherein the inducer is coupled to the second gear train.
9. The gas turbine engine according to claim 8, wherein the inducer is rotationally fixed relative to the fan.
10. The gas turbine engine according to claim 1, wherein the inducer is configured to rotate at a different rotational speed than the first compressor section.
11. The gas turbine engine according to claim 10, wherein the inducer is configured to rotate at a different rotational speed than the fan.
12. The gas turbine engine according to claim 1, wherein the inducer is configured to rotate at a different rotational speed than the fan.
13. A gas turbine engine comprising:
first and second shafts rotatable about a common axis;
a first turbine section supported on the first shaft;
second compressor and turbine sections supported on the second shaft;
a fan;
a first compressor section arranged in an axial flow relationship with the second compressor and the first and second turbines;
a geared architecture operatively connecting the first shaft and the fan, the geared architecture includes first and second gear trains, the first gear train an epicyclic gear train, and the second gear train configured to provide a speed reduction;
an inducer operative coupled to the gear train;
a bypass flow path and a core flow path, the first and second compressor and turbine sections arranged in the core flow path, and the fan extending into the bypass flow path, the inducer arranged in the core flow path outside of the bypass flow path and upstream from the first compressor section; and
wherein the first and second shafts respectively provide low and high spools, and the first compressor and turbine sections are low pressure compressor and turbine sections, and the second compressor and turbine sections are high pressure compressor and turbine sections.
14. The gas turbine engine according to claim 13, wherein the inducer is coupled to the first gear train, the epicyclic gear train is a differential gear train that includes a sun gear, planetary gears arranged about and intermeshing with the sun gear, and a ring gear circumscribing and intermeshing with the planetary gears.
15. The gas turbine engine according to claim 14, wherein the inducer is rotationally fixed relative to the ring gear.
16. The gas turbine engine according to claim 14, wherein the inducer is rotationally fixed relative to the star gear.
17. The gas turbine engine according to claim 13, wherein the inducer is coupled to the second gear train.
18. The gas turbine engine according to claim 17, wherein the inducer is rotationally fixed relative to the fan.
19. The gas turbine engine according to claim 13, wherein the inducer is configured to rotate at a different rotational speed than the first compressor section.
20. The gas turbine engine according to claim 19, wherein the inducer is configured to rotate at a different rotational speed than the fan.
21. The gas turbine engine according to claim 13, wherein the inducer is configured to rotate at a different rotational speed than the fan.
PCT/US2013/033960 2012-04-02 2013-03-27 Geared architecture with inducer for gas turbine engine WO2014143074A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
EP13877780.0A EP2834505B1 (en) 2012-04-02 2013-03-27 Geared architecture with inducer for gas turbine engine

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US13/437,395 US10018119B2 (en) 2012-04-02 2012-04-02 Geared architecture with inducer for gas turbine engine
US13/437,395 2012-04-02

Publications (1)

Publication Number Publication Date
WO2014143074A1 true WO2014143074A1 (en) 2014-09-18

Family

ID=49235273

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US2013/033960 WO2014143074A1 (en) 2012-04-02 2013-03-27 Geared architecture with inducer for gas turbine engine

Country Status (3)

Country Link
US (2) US10018119B2 (en)
EP (1) EP2834505B1 (en)
WO (1) WO2014143074A1 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP3101258B1 (en) 2015-06-05 2020-01-08 United Technologies Corporation Geared architecture for a gas turbine engine and a corresponding method

Families Citing this family (18)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US10036316B2 (en) * 2012-10-02 2018-07-31 United Technologies Corporation Geared turbofan engine with high compressor exit temperature
WO2014126696A1 (en) * 2013-02-13 2014-08-21 United Technologies Corporation Gas turbine engine geared architecture
US10287976B2 (en) * 2014-07-15 2019-05-14 United Technologies Corporation Split gear system for a gas turbine engine
US11225913B2 (en) 2015-02-19 2022-01-18 Raytheon Technologies Corporation Method of providing turbine engines with different thrust ratings
US20160245184A1 (en) * 2015-02-19 2016-08-25 United Technologies Corporation Geared turbine engine
US10669947B2 (en) 2016-07-11 2020-06-02 Raytheon Technologies Corporation Geared gas turbine engine
US10760592B1 (en) * 2017-01-17 2020-09-01 Raytheon Technologies Corporation Gas turbine engine airfoil frequency design
US10760429B1 (en) * 2017-01-17 2020-09-01 Raytheon Technologies Corporation Gas turbine engine airfoil frequency design
US10788049B1 (en) * 2017-01-17 2020-09-29 Raytheon Technologies Corporation Gas turbine engine airfoil frequency design
FR3086348B1 (en) * 2018-09-21 2020-12-04 Safran Aircraft Engines REDUCER TURBOREACTOR
US11891967B2 (en) 2018-09-21 2024-02-06 Safran Aircraft Engines Turbofan comprising a power supply device to drive the compressor
GB201820925D0 (en) * 2018-12-21 2019-02-06 Rolls Royce Plc Turbine engine
GB201820924D0 (en) 2018-12-21 2019-02-06 Rolls Royce Plc Turbine engine
US11204037B2 (en) 2018-12-21 2021-12-21 Rolls-Royce Plc Turbine engine
US11041462B2 (en) 2019-06-05 2021-06-22 Raytheon Technologies Corporation Hybrid turbofan with differential electrical and mechanical power transfer
US11623756B2 (en) * 2019-12-20 2023-04-11 Pratt & Whitney Canada Corp. Gas turbine engine with variable speed output
FR3127256A1 (en) * 2021-09-21 2023-03-24 Safran Transmission Systems POWER TRANSMISSION MODULE FOR AN AIRCRAFT TURBOMACHINE
JP2023050943A (en) * 2021-09-30 2023-04-11 三菱重工コンプレッサ株式会社 Planetary gear mechanism and rotor machine system

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20090145102A1 (en) 2007-12-05 2009-06-11 United Technologies Corp. Gas Turbine Engine Systems Involving Tip Fans
US20090148276A1 (en) * 2004-12-01 2009-06-11 Suciu Gabriel L Seal assembly for a fan rotor of a tip turbine engine
US20090288421A1 (en) * 2008-05-21 2009-11-26 Honeywell International Inc. Turbine drive system with lock-up clutch and method
US20100005778A1 (en) * 2006-10-12 2010-01-14 Zaffir Chaudhry Fan variable area nozzle with cable actuator system
US20100192595A1 (en) * 2009-01-30 2010-08-05 Robert Joseph Orlando Gas turbine engine assembly and methods of assembling same

Family Cites Families (47)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB579820A (en) 1943-06-22 1946-08-16 Frank Robert Bell Improvements in or relating to power-gas-generators for internal-combustion power units
US2801518A (en) 1952-09-17 1957-08-06 Solar Aircraft Co Gas turbine
DE1124823B (en) 1959-05-02 1962-03-01 Daimler Benz Ag Propulsion for aircraft
US3287906A (en) 1965-07-20 1966-11-29 Gen Motors Corp Cooled gas turbine vanes
GB1097632A (en) 1965-11-19 1968-01-03 Bristol Siddeley Engines Ltd Gas turbine power plant
GB1484898A (en) 1974-09-11 1977-09-08 Rolls Royce Ducted fan gas turbine engine
GB1516041A (en) 1977-02-14 1978-06-28 Secr Defence Multistage axial flow compressor stators
GB2041090A (en) 1979-01-31 1980-09-03 Rolls Royce By-pass gas turbine engines
US4251987A (en) 1979-08-22 1981-02-24 General Electric Company Differential geared engine
US5010729A (en) * 1989-01-03 1991-04-30 General Electric Company Geared counterrotating turbine/fan propulsion system
DE4122008A1 (en) * 1991-07-03 1993-01-14 Mtu Muenchen Gmbh GAUGE ENGINE WITH COUNTER-PRESSURE LOW-PRESSURE COMPRESSOR (BOOSTER)
GB2259328B (en) 1991-09-03 1995-07-19 Gen Electric Gas turbine engine variable bleed pivotal flow splitter
US5915917A (en) 1994-12-14 1999-06-29 United Technologies Corporation Compressor stall and surge control using airflow asymmetry measurement
US5806303A (en) * 1996-03-29 1998-09-15 General Electric Company Turbofan engine with a core driven supercharged bypass duct and fixed geometry nozzle
DE19828562B4 (en) * 1998-06-26 2005-09-08 Mtu Aero Engines Gmbh Engine with counter-rotating rotors
US6895741B2 (en) 2003-06-23 2005-05-24 Pratt & Whitney Canada Corp. Differential geared turbine engine with torque modulation capability
US20050005664A1 (en) 2003-07-09 2005-01-13 Wesley Scott System and method for bending strip material to create cutting dies
US6901739B2 (en) * 2003-10-07 2005-06-07 General Electric Company Gas turbine engine with variable pressure ratio fan system
FR2866387B1 (en) * 2004-02-12 2008-03-14 Snecma Moteurs AERODYNAMIC ADAPTATION OF THE BACK BLOW OF A DOUBLE BLOWER TURBOREACTOR
DE602004027766D1 (en) 2004-12-01 2010-07-29 United Technologies Corp HYDRAULIC SEAL FOR A GEARBOX OF A TOP TURBINE ENGINE
WO2006059992A1 (en) 2004-12-01 2006-06-08 United Technologies Corporation Inducer for a fan blade of a tip turbine engine
WO2006059993A1 (en) 2004-12-01 2006-06-08 United Technologies Corporation Tip turbine engine with multiple fan and turbine stages
US8061968B2 (en) 2004-12-01 2011-11-22 United Technologies Corporation Counter-rotating compressor case and assembly method for tip turbine engine
WO2006059986A1 (en) 2004-12-01 2006-06-08 United Technologies Corporation Tip turbine engine and operating method with reverse core airflow
WO2006059968A1 (en) 2004-12-01 2006-06-08 United Technologies Corporation Counter-rotating gearbox for tip turbine engine
EP1825117B1 (en) * 2004-12-01 2012-06-13 United Technologies Corporation Turbine engine with differential gear driven fan and compressor
US7959406B2 (en) 2004-12-01 2011-06-14 United Technologies Corporation Close coupled gearbox assembly for a tip turbine engine
WO2006060005A1 (en) 2004-12-01 2006-06-08 United Technologies Corporation Fan-turbine rotor assembly with integral inducer section for a tip turbine engine
WO2006059985A1 (en) 2004-12-01 2006-06-08 United Technologies Corporation Axial compressor for tip turbine engine
DE102005018139A1 (en) * 2005-04-20 2006-10-26 Mtu Aero Engines Gmbh Jet engine
US20070205321A1 (en) 2005-06-24 2007-09-06 Karem Aircraft, Inc. Speed changing gearbox with dual path input
US8772398B2 (en) 2005-09-28 2014-07-08 Entrotech Composites, Llc Linerless prepregs, composite articles therefrom, and related methods
US7513103B2 (en) * 2005-10-19 2009-04-07 General Electric Company Gas turbine engine assembly and methods of assembling same
US7752836B2 (en) * 2005-10-19 2010-07-13 General Electric Company Gas turbine assembly and methods of assembling same
GB0614302D0 (en) * 2006-07-19 2006-08-30 Rolls Royce Plc An engine arrangement
EP3128164B1 (en) * 2006-08-22 2019-07-10 Rolls-Royce North American Technologies, Inc. Gas turbine engine with intermediate speed booster
US7841165B2 (en) 2006-10-31 2010-11-30 General Electric Company Gas turbine engine assembly and methods of assembling same
US7788898B2 (en) 2006-12-06 2010-09-07 General Electric Company Variable coupling of turbofan engine spools via open differential gear set or simple planetary gear set for improved power extraction and engine operability, with torque coupling for added flexibility
US7716914B2 (en) * 2006-12-21 2010-05-18 General Electric Company Turbofan engine assembly and method of assembling same
WO2008082336A1 (en) 2006-12-29 2008-07-10 Volvo Aero Corporation A power transmission device for a gas turbine engine, an aeroplane and a method for operating a gas turbine engine
US8017188B2 (en) 2007-04-17 2011-09-13 General Electric Company Methods of making articles having toughened and untoughened regions
US8104265B2 (en) * 2007-06-28 2012-01-31 United Technologies Corporation Gas turbines with multiple gas flow paths
US8205432B2 (en) 2007-10-03 2012-06-26 United Technologies Corporation Epicyclic gear train for turbo fan engine
US8166748B2 (en) * 2008-11-21 2012-05-01 General Electric Company Gas turbine engine booster having rotatable radially inwardly extending blades and non-rotatable vanes
US8191352B2 (en) 2008-12-19 2012-06-05 General Electric Company Geared differential speed counter-rotatable low pressure turbine
GB0903935D0 (en) * 2009-03-09 2009-04-22 Rolls Royce Plc Gas turbine engine
US8172716B2 (en) 2009-06-25 2012-05-08 United Technologies Corporation Epicyclic gear system with superfinished journal bearing

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20090148276A1 (en) * 2004-12-01 2009-06-11 Suciu Gabriel L Seal assembly for a fan rotor of a tip turbine engine
US20100005778A1 (en) * 2006-10-12 2010-01-14 Zaffir Chaudhry Fan variable area nozzle with cable actuator system
US20090145102A1 (en) 2007-12-05 2009-06-11 United Technologies Corp. Gas Turbine Engine Systems Involving Tip Fans
US20090288421A1 (en) * 2008-05-21 2009-11-26 Honeywell International Inc. Turbine drive system with lock-up clutch and method
US20100192595A1 (en) * 2009-01-30 2010-08-05 Robert Joseph Orlando Gas turbine engine assembly and methods of assembling same

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP3101258B1 (en) 2015-06-05 2020-01-08 United Technologies Corporation Geared architecture for a gas turbine engine and a corresponding method

Also Published As

Publication number Publication date
EP2834505B1 (en) 2019-05-01
US20180363565A1 (en) 2018-12-20
US10584642B2 (en) 2020-03-10
US20130259652A1 (en) 2013-10-03
US10018119B2 (en) 2018-07-10
EP2834505A1 (en) 2015-02-11
EP2834505A4 (en) 2015-04-29

Similar Documents

Publication Publication Date Title
US10584642B2 (en) Geared architecture with inducer for gas turbine engine
EP2834504B1 (en) Geared architecture with speed change device for gas turbine engine
EP2834496B1 (en) Differential geared architecture for gas turbine engine
CA2879756C (en) Geared fan with inner counter rotating compressor
US9816442B2 (en) Gas turbine engine with high speed low pressure turbine section
US20200049077A1 (en) Gas turbine engine with high speed low pressure turbine section and bearing support features
EP3036416B1 (en) High thrust geared gas turbine engine
CA2854077C (en) Gas turbine engine with high speed low pressure turbine section and bearing support features
US20210010426A1 (en) Gear reduction for lower thrust geared turbofan
EP2809934A2 (en) Gas turbine engine with high speed low pressure turbine section
WO2014078157A1 (en) Gas turbine engine with mount for low pressure turbine section
WO2014018142A2 (en) Gas turbine engine with high speed low pressure turbine section and bearing support features
WO2014204526A2 (en) Family of geared turbo fan engines
US20160053679A1 (en) Gas turbine engine with high speed low pressure turbine section and bearing support features
EP3165755A1 (en) Gas turbine engine with high speed low pressure turbine section and bearing support features

Legal Events

Date Code Title Description
NENP Non-entry into the national phase

Ref country code: DE

WWE Wipo information: entry into national phase

Ref document number: 2013877780

Country of ref document: EP

121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 13877780

Country of ref document: EP

Kind code of ref document: A1