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GB2471845A - Fan outlet guide vane arrangement in a turbofan gas turbine engine - Google Patents

Fan outlet guide vane arrangement in a turbofan gas turbine engine Download PDF

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Publication number
GB2471845A
GB2471845A GB0912166A GB0912166A GB2471845A GB 2471845 A GB2471845 A GB 2471845A GB 0912166 A GB0912166 A GB 0912166A GB 0912166 A GB0912166 A GB 0912166A GB 2471845 A GB2471845 A GB 2471845A
Authority
GB
United Kingdom
Prior art keywords
outlet guide
fan
fan outlet
guide vane
gas turbine
Prior art date
Legal status (The legal status 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 status listed.)
Withdrawn
Application number
GB0912166A
Other versions
GB0912166D0 (en
Inventor
Nicholas David Humprheys
Peter Jean Gabriel Schwaller
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Rolls Royce PLC
Original Assignee
Rolls Royce PLC
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 Rolls Royce PLC filed Critical Rolls Royce PLC
Priority to GB0912166A priority Critical patent/GB2471845A/en
Publication of GB0912166D0 publication Critical patent/GB0912166D0/en
Publication of GB2471845A publication Critical patent/GB2471845A/en
Withdrawn legal-status Critical Current

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01D—NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
    • F01D17/00—Regulating or controlling by varying flow
    • F01D17/10—Final actuators
    • F01D17/12—Final actuators arranged in stator parts
    • F01D17/14—Final actuators arranged in stator parts varying effective cross-sectional area of nozzles or guide conduits
    • F01D17/16—Final actuators arranged in stator parts varying effective cross-sectional area of nozzles or guide conduits by means of nozzle vanes
    • F01D17/162—Final actuators arranged in stator parts varying effective cross-sectional area of nozzles or guide conduits by means of nozzle vanes for axial flow, i.e. the vanes turning around axes which are essentially perpendicular to the rotor centre line
    • 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
    • F02C3/00—Gas-turbine plants characterised by the use of combustion products as the working fluid
    • F02C3/04—Gas-turbine plants characterised by the use of combustion products as the working fluid having a turbine driving a compressor
    • F02C3/10—Gas-turbine plants characterised by the use of combustion products as the working fluid having a turbine driving a compressor with another turbine driving an output shaft but not driving the compressor
    • 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
    • F02C7/04—Air intakes for gas-turbine plants or jet-propulsion plants
    • F02C7/045—Air intakes for gas-turbine plants or jet-propulsion plants having provisions for noise suppression
    • 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

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Structures Of Non-Positive Displacement Pumps (AREA)

Abstract

A turbofan gas turbine engine 10 comprises a fan, a fan casing 28 and a fan outlet guide vane assembly 34. The fan comprises a fan rotor 24 carrying a plurality of circumferentially spaced radially outwardly extending fan blades 26. The fan casing 28 surrounds the fan and defines a fan duct 30. The fan outlet guide vane assembly 34 comprising a plurality of circumferentially spaced radially extending fan outlet guide vanes 36 and the fan outlet guide vanes 36 are secured to the fan casing 28. The ratio of the number of fan outlet guide vanes 36 to the number of fan blades 26 is equal to orgreater than 0.4 and equal to or less than 0.75. This reduces broadband noise and acoustic liners 40 may be provided on the fan outlet guide vanes 36 to reduce blade passing frequency noise.

Description

A TURBOFAN GAS TURBINE ENGINE
The present invention relates to a turbofan gas turbine engine.
Currently turbofan gas turbine engines have about twice as many fan outlet guide vanes as fan blades. This ratio of the number of fan outlet guide vanes to fan blades is chosen so as to "cut off" the blade passing frequency noise produced by the fan of the turbofan gas turbine engine.
However, the use of a large number of fan outlet guide vanes adds cost and weight to the turbofan gas turbine engine.
Accordingly the present invention seeks to provide a novel turbofan gas turbine engine which reduces, preferably overcomes, the above mentioned problem.
Accordingly the present invention provides a turbofan gas turbine engine comprising a fan, a fan casing and a fan outlet guide vane assembly, the fan comprising a fan rotor carrying a plurality of crcumferentially spaced radially outwardly extending fan blades, the fan casing surrounding the fan and defining a fan duct, the fan outlet guide vane assembly comprising a plurality of circumferentially spaced radially extending fan outlet guide vanes, the fan outlet guide vanes being secured to the fan casing, the ratio of the number of fan outlet guide vanes to the number of fan blades being equal to or greater than 0.4 and equal to or less than 0.75 or the ratio of the number of fan outlet guide vanes to the number of fan blades being equal to or greater than 0.2 and equal to or less than 0.33.
Preferably the ratio of the number of fan outlet guide vanes to the number of fan blades being equal to or greater than 0.4 and equal to or less than 0.6.
Preferably the ratio of the number of fan outlet guide vanes to the number of fan blades being equal to or greater than 0.45 and equal to or less than 0.55.
Preferably the ratio of the number of fan outlet guide vanes to the number of fan blades being equal to 0.5.
Preferably at least a portion of at least one of the fan outlet guide vanes comprises an acoustic liner.
Preferably at least a portion of each fan outlet guide vane comprises an acoustic liner.
Preferably the acoustic liner is arranged on a concave surface and/or a convex surface of the at least one fan outlet guide vane.
Preferably the acoustic liner comprises a perforate wall, an imperforate backing wall and a honeycomb structure arranged between the perforate wall and the imperforate backing wall.
Preferably the perforate wall of the acoustic liner defines a perforate wall of the convex surface and/or the concave surface of the at least one fan outlet guide vane, the honeycomb structure and the imperforate backing wall being arranged within the at least one fan cutlet guide vane.
Preferably the leading edge of the at least one fan outlet guide vane is imperforate.
Preferably the leading edge of the at least one fan outlet guide vane has anti-icing means. Preferably the anti-icing means comprises an electrical heater or a supply of hot fluid.
Preferably the leading edge of the at least one fan outlet guide vane is radially swept and/or the leading edge of the at least one fan outlet guide vane is leant circumferentially.
Preferably the radially outer end of the leading edge of the at least one fan outlet guide vane is arranged axially downstream of the radially inner end of the leading edge of the at least one fan outlet guide vane. Preferably the radially outer end of leading edge of each fan outlet guide vane is arranged axially downstream of the radially inner end of the leading edge of the fan outlet guide vane.
Alternatively the radially outer end of the leading edge of the at least one fan outlet guide vane is arranged axially upstream of the radially inner end of the leading edge of the at least one fan outlet guide vane. The radially outer end of the leading edge of each fan outlet guide vane is arranged axially upstream of the radially inner end of the leading edge of the fan outlet guide vane.
Preferably the outer end of leading edge of the at least one fan outlet guide vane is arranged circumferentially displaced from the radially inner end of the leading edge of the at least one fan outlet guide vane.
Preferably the outer end of leading edge of each fan outlet guide vane is arranged circumferentially displaced from the radially inner end of the leading edge of the fan outlet guide vane.
The present invention will be more fully described by way of example with reference to the accompanying drawings in which:-Figure 1 shows a turbofan gas turbine engine according to the present invention.
Figure 2 is an enlarged view of a fan cutlet guide vane of a turbofan gas turbine engine according to the present invention.
Figure 3 is an enlarged cross-sectional view in the direction of arrows A-A in figure 2.
Figure 4 is a view in the direction of arrow B in figure 2.
A turbofan gas turbine engine 10, as shown in figure 1, comprises in axial flow series an inlet 12, a fan section 14, a compressor section 16, a combustion section 18, a turbine section 20 and an exhaust 22. The fan section 14 comprises a fan rotor 24, which carries a plurality of circumferentially spaced radially outwardly extending fan blades 26. The fan rotor 24 and the fan blades 26 are surrounded by a fan casing 28 to define the outer extremity of a fan duct 30. The compressor section 16 comprises an intermediate pressure compressor (not shown) and a high pressure compressor (not shown) . The turbine section 20 section comprises a high pressure turbine (not shown), an intermediate pressure turbine (not shown) and a low pressure turbine (not shown) . The low pressure turbine is arranged to drive the fan rotor 24 and fan blades 26 via a shaft (not shown), the intermediate pressure turbine is arranged to drive the intermediate pressure compressor via a shaft (not shown) and the high pressure turbine is arranged to drive the high pressure compressor via a shaft (not shown) . The compressor section 16, the combustion section 18 and the turbine section 20 are enclosed in a core engine casing 32. A fan outlet guide vane assembly 34 secures the fan casing 28 to the core engine casing 32. The fan outlet guide vane assembly 34 comprises a plurality of circumferentially spaced radially extending fan outlet guide vanes 36. The radially outer ends 35 of the fan outlet guide vanes 36 are secured to the fan casing 28 and the radially inner ends 37 of the fan outlet guide vanes 36 are secured to the core engine casing 32. The turbofan gas turbine engine 10 operates quite conventionally.
In the present invention the ratio of the number of fan outlet guide vanes 36 to the number of fan blades 26 is equal to or greater than 0.4 and equal to or less than 0.75 or the ratio of the number of fan outlet guide vanes to the number of fan blades being equal to or greater than 0.2 and equal to or less than 0.33. Preferably the ratio of the number of fan outlet guide vanes 36 to the number of fan blades 26 is equal to or greater than 0.4 and equal to or less than 0.6. More preferably the ratio of the number of fan outlet guide vanes 36 to the number of fan blades 26 is equal to or greater than 0.45 and equal to or less than 0.55. It is most preferred that the ratio of the number of fan outlet guide vanes 36 to the number of fan blades 26 is equal to 0.5.
At least a portion 38 of at least one of the fan outlet guide vanes 36 comprises an acoustic liner 40, as shown in figures 2 and 3, in particular at least a portion 38 of each fan outlet guide vane 36 comprises an acoustic liner 40. The acoustic liner 40 is arranged on a concave surface 42 and/or a convex surface 44 of the at least one fan outlet guide vane 36.
The acoustic liner 40 may comprise a perforate wall 50, an imperforate backing wall 52 and a honeycomb structure 54 arranged between the perforate wall 50 and the imperforate backing wall 52. The perforate wall 50 of the acoustic liner 40 defines a perforate wall of the convex surface 42 and/or the concave surface 44 of the at least one fan outlet guide vane 36, the honeycomb structure 54 and the imperforate backing wall 52 are arranged within the at least one fan outlet guide vane 36. The leading edge 46 of the at least one fan outlet guide vane 36 is imperforate. The leading edge 46 of the at least one fan outlet guide vane 36 has anti-icing means 56. The anti-icing means 56 comprises an electrical heater or a supply of hot fluid.
The leading edge 46 of the at least one fan outlet guide vane 36 is radially swept, as shown in figure 2, and/or the leading edge 46 of the at least one fan outlet guide vane 36 is leant circumferentially, as shown in figure 4.
The radially outer end 35 of the leading edge 46 of the at least one fan outlet guide vane 36 is arranged axially downstream of the radially inner end 37 of the leading edge 46 of the at least one fan outlet guide vane 36. The radially outer end 35 of leading edge 46 of each fan outlet guide vane 36 is arranged axially downstream of the radially inner end 37 of the leading edge 46 of the fan outlet guide vane 36. The leading edges 46 of the fan outlet guide vanes 36 may be arranged to be linear curves or non-linear curves, e.g. polynomial curves or other complex shapes.
The radially outer end 35 of the leading edge 46 of the at least one fan outlet guide vane 36 is arranged to be circumferentially displaced from the radially inner end 37 of the leading edge 46 of the at least one fan outlet guide vane 36. The outer end 35 of leading edge 46 of each fan outlet guide vane 36 is arranged to be circumferentially displaced from the radially inner end 37 of the leading edge 46 of the fan outlet guide vane 36. The leading edges 46 of the fan outlet guide vanes 36 may be arranged to be linear curves or non-linear curves, e.g. polynomial curves.
As an example a turbofan gas turbine engine has twenty seven fan blades 26 and preferably the number of fan outlet guide vanes 36 is 0.5 times the number of fan blades 26, therefore there are thirteen or fourteen fan outlet guide vanes 36. The number of fan outlet guide vanes 36 may be between 0.4 and 0.6 times the number of fan blades 26, therefore there may be eleven or sixteen fan outlet guide vanes 36 or any number in between. The number of fan outlet guide vanes 36 may be between 0.2 and 0.33 the number of fan blades 26, therefore there may be five or nine fan outlet guide vanes 36 or any number in between.
The number of fan outlet guide vanes 36 may be 0.75 times the number of fan blades 26, therefore there may be twenty fan outlet guide vanes 36 or any number between sixteen and twenty.
The acoustic liner 40 may be arranged to reduce noise at the blade passing frequency. The fan outlet guide vanes may be cyclically staggered, e.g. the axial positions of and/or the circumferential spacing between, the fan outlet guide vanes may vary circumferentially around the fan outlet guide vane assembly to reduce noise from any obstructions, e.g. a pylon, downstream of the fan outlet guise vane assembly.
The advantage of the present invention is that there is a reduced number of fan outlet guide vanes and this reduces cost and weight. The reduced number of fan outlet guide vanes requires that the fan outlet guide vanes become thicker and must have a longer chord length and may be combined with the structural elements e.g. the fan casing and core casing. The longer chord length fan outlet guide vanes may also have services, e.g. fuel pipes, oil pipes, hydraulic pipes, air pipes, electrical cables etc, extending generally radially there-through to and from the core engine. The longer chord length of the fan outlet guide vane may be provided with an acoustic liner to absorb noise, particularly the band passing frequency noise. The leading edges of the fan outlet guide vanes may remain imperforate to maintain aerodynamic performance by maintaining a laminar flow at the leading edge of the fan outlet guide vanes and the acoustic liner are positioned further downstream beyond the point of transition to turbulent flow. The leading edges of the fan outlet guide vanes may be provided with heaters, if necessary, to prevent and/or control the formation of ice on the leading edges of the fan outlet guide vanes. Alternatively the leading edges may be perforate. The leading edges of the fan outlet guide vanes are swept and or leant tangentially, circumferentially, to take advantage of wake noise reduction. The radially outer end of the leading edge of each fan outlet guide vane is arranged axially upstream, or axially downstream, of the radially inner end of the leading edge of the fan outlet guide vane. The fan outlet guide vane assembly of the present invention has reduced broadband noise and reduced high frequency fan harmonic noise compared to a fan outlet guide vane assembly with a ratio of fan outlet guide vanes to fan blades of two or more, but the blade passing frequency noise of a fan outlet guide vane assembly of the present invention has increased blade passing frequency noise compared to a fan outlet guide vane assembly with a ratio of fan outlet guide vanes to fan blades of two or more. Broadband noise is becoming more important in modern turbofan gas turbine engines. The present invention combines the advantage of broadband noise reduction provided by a lower number of fan outlet guide vanes with the provision of acoustic liners on the fan outlet guide vanes and swept/leant fan outlet guide vanes to reduce the blade passing frequency noise.
The present invention is also applicable to a turbofan gas turbine engine comprising a fan, a high pressure compressor, a high pressure turbine and a low pressure turbine.

Claims (18)

  1. Claims: - 1. A turbofan gas turbine engine comprising a fan, a fan casing and a fan outlet guide vane assembly, the fan comprising a fan rotor carrying a plurality of circumferentially spaced radially outwardly extending fan blades, the fan casing surrounding the fan and defining a fan duct, the fan outlet guide vane assembly comprising a plurality of circumferentially spaced radially extending fan outlet guide vanes, the fan outlet guide vanes being secured to the fan casing, the ratio of the number of fan outlet guide vanes to the number of fan blades being equal to or greater than 0.4 and equal to or less than 0.75 or the ratio of the number of fan outlet guide vanes to the number of fan blades being equal to or greater than 0.2 and equal to or less than 0.33.
  2. 2. A turbofan gas turbine engine as claimed in claim 1 wherein the ratio of the number of fan outlet guide vanes to the number of fan blades being equal to or greater than 0.4 and equal to or less than 0.6.
  3. 3. A turbofan gas turbine engine as claimed in claim 1 or claim 2 wherein the ratio of the number of fan outlet guide vanes to the number of fan blades being equal to or greater than 0.45 and equal to or less than 0.55.
  4. 4. A turbofan gas turbine engine as claimed in claim 1, claim 2 or claim 3 wherein the ratio of the number of fan outlet guide vanes to the number of fan blades being equal to 0.5.
  5. 5. A turbofan gas turbine engine as claimed in any of claims 1 to 4 wherein at least a portion of at least one of the fan outlet guide vanes comprises an acoustic liner.
  6. 6. A turbofan gas turbine engine as claimed in claim 5 wherein at least a portion of each fan outlet guide vane comprises an acoustic liner.
  7. 7. A turbofan gas turbine engine as claimed in claim 5 or claim 6 wherein the acoustic liner is arranged on a concave surface and/or a convex surface of the at least one fan outlet guide vane.
  8. 8. A turbofan gas turbine engine as claimed in claim 5, claim 6 or claim 7 wherein the acoustic liner comprises a perforate wall, an imperforate backing wall and a honeycomb structure arranged between the perforate wall and the imperforate backing wall.
  9. 9. A turbofan gas turbine engine as claimed in claim 8 wherein the perforate wall of the acoustic liner defines a perforate wall of the convex surface and/or the concave surface of the at least one fan outlet guide vane, the honeycomb structure and the imperforate backing wall being arranged within the at least one fan outlet guide vane.
  10. 10. A turbofan gas turbine engine as claimed in any of claims 5 to 9 wherein the leading edge of the at least one fan outlet guide vane is imperforate.
  11. 11. A turbofan gas turbine engine as claimed in claim 10 wherein the leading edge of the at least one fan outlet guide vane has anti-icing means.
  12. 12. A turbofan gas turbine engine as claimed in claim 11 wherein the anti-icing means comprises an electrical heater or a supply of hot fluid.
  13. 13. A turbofan gas turbine engine as claimed in any of claims 1 to 12 wherein the leading edge of the at least one fan outlet guide vane is radially swept and/or the leading edge of the at least one fan outlet guide vane is leant circumferentially.
  14. 14. A turbofan gas turbine engine as claimed in claim 13 wherein the radially outer end of the leading edge of the at least one fan outlet guide vane is arranged axially downstream of the radially inner end of the leading edge of the at least one fan outlet guide vane.
  15. 15. A turbofan gas turbine engine as claimed in claim 14 wherein the radially outer end of the leading edge of each fan outlet guide vane is arranged axially downstream of the radially inner end of the leading edge of the fan outlet guide vane.
  16. 16. A turbofan gas turbine engine as claimed in any of claims 13 to 15 wherein the outer end of leading edge of the at least one fan outlet guide vane is arranged circumferentially displaced from the radially inner end of the leading edge of the at least one fan outlet guide vane.
  17. 17. A turbofan gas turbine engine as claimed in claim 16 wherein the outer end of leading edge of each fan outlet guide vane is arranged circumferentially displaced from the radially inner end of the leading edge of the fan outlet guide vane.
  18. 18. A turbofan gas turbine engine substantially as hereinbefore described with reference to and as shown in the accompanying drawings.
GB0912166A 2009-07-14 2009-07-14 Fan outlet guide vane arrangement in a turbofan gas turbine engine Withdrawn GB2471845A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
GB0912166A GB2471845A (en) 2009-07-14 2009-07-14 Fan outlet guide vane arrangement in a turbofan gas turbine engine

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB0912166A GB2471845A (en) 2009-07-14 2009-07-14 Fan outlet guide vane arrangement in a turbofan gas turbine engine

Publications (2)

Publication Number Publication Date
GB0912166D0 GB0912166D0 (en) 2009-08-26
GB2471845A true GB2471845A (en) 2011-01-19

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Cited By (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2013130295A1 (en) 2012-02-29 2013-09-06 United Technologies Corporation Geared gas turbine engine with reduced fan noise
US10107191B2 (en) 2012-02-29 2018-10-23 United Technologies Corporation Geared gas turbine engine with reduced fan noise
EP3799030A1 (en) * 2019-09-26 2021-03-31 Rolls-Royce Deutschland Ltd & Co KG Acoustic liner and gas turbine engine with such acoustic liner
US11230928B1 (en) 2020-07-22 2022-01-25 Raytheon Technologies Corporation Guide vane with truss structure and honeycomb
US20220049656A1 (en) * 2020-08-14 2022-02-17 Raytheon Technologies Corporation Active flow control transpirational flow acoustically lined guide vane
US11512608B2 (en) 2020-08-14 2022-11-29 Raytheon Technologies Corporation Passive transpirational flow acoustically lined guide vane
US11566564B2 (en) 2020-07-08 2023-01-31 Raytheon Technologies Corporation Acoustically treated panels
US11781485B2 (en) 2021-11-24 2023-10-10 Rtx Corporation Unit cell resonator networks for gas turbine combustor tone damping
US11804206B2 (en) 2021-05-12 2023-10-31 Goodrich Corporation Acoustic panel for noise attenuation
US11830467B2 (en) 2021-10-16 2023-11-28 Rtx Coroporation Unit cell resonator networks for turbomachinery bypass flow structures
US12085023B2 (en) 2022-10-03 2024-09-10 General Electric Company Circumferentially varying fan casing treatments for reducing fan noise effects
US12092034B2 (en) 2022-10-03 2024-09-17 General Electric Company Circumferentially varying fan casing treatments for reducing fan noise effects
US12104536B2 (en) 2021-05-12 2024-10-01 Rohr, Inc. Nacelle liner comprising unit cell resonator networks
US12118971B2 (en) 2021-05-12 2024-10-15 B/E Aerospace, Inc. Aircraft acoustic panel
US20250052163A1 (en) * 2023-08-09 2025-02-13 General Electric Company Turbofan engine including integrated pylon and fan outlet guide vane with noise reduction features

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Publication number Priority date Publication date Assignee Title
US3883264A (en) * 1971-04-08 1975-05-13 Gadicherla V R Rao Quiet fan with non-radial elements
GB1445384A (en) * 1972-10-02 1976-08-11 United Aircraft Corp Ducted fan'ssembly having noise reduction means
GB2259334A (en) * 1991-09-06 1993-03-10 Gen Electric Low noise fan assembly.
FR2681644A1 (en) * 1991-09-20 1993-03-26 Onera (Off Nat Aerospatiale) Improvements made to fans (blowers) particularly for turbojets with at least one bypass flow
DE102006060694A1 (en) * 2006-12-18 2008-06-19 Rolls-Royce Deutschland Ltd & Co Kg Compressor stage of a gas turbine aero engine has structured number of fan rotor and stator vanes to prevent pressure fields building up between the vanes

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3883264A (en) * 1971-04-08 1975-05-13 Gadicherla V R Rao Quiet fan with non-radial elements
GB1445384A (en) * 1972-10-02 1976-08-11 United Aircraft Corp Ducted fan'ssembly having noise reduction means
GB2259334A (en) * 1991-09-06 1993-03-10 Gen Electric Low noise fan assembly.
FR2681644A1 (en) * 1991-09-20 1993-03-26 Onera (Off Nat Aerospatiale) Improvements made to fans (blowers) particularly for turbojets with at least one bypass flow
DE102006060694A1 (en) * 2006-12-18 2008-06-19 Rolls-Royce Deutschland Ltd & Co Kg Compressor stage of a gas turbine aero engine has structured number of fan rotor and stator vanes to prevent pressure fields building up between the vanes

Cited By (23)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2013130295A1 (en) 2012-02-29 2013-09-06 United Technologies Corporation Geared gas turbine engine with reduced fan noise
EP2820270A4 (en) * 2012-02-29 2015-12-02 United Technologies Corp REDUCING GAS TURBINE WITH REDUCED BLOW NOISE
US10107191B2 (en) 2012-02-29 2018-10-23 United Technologies Corporation Geared gas turbine engine with reduced fan noise
US10655538B2 (en) 2012-02-29 2020-05-19 United Technologies Corporation Geared gas turbine engine with reduced fan noise
US11118507B2 (en) 2012-02-29 2021-09-14 Raytheon Technologies Corporation Geared gas turbine engine with reduced fan noise
US11512631B2 (en) 2012-02-29 2022-11-29 Raytheon Technologies Corporation Geared gas turbine engine with reduced fan noise
EP3799030A1 (en) * 2019-09-26 2021-03-31 Rolls-Royce Deutschland Ltd & Co KG Acoustic liner and gas turbine engine with such acoustic liner
US12134996B2 (en) 2019-09-26 2024-11-05 Rolls-Royce Deutschland Ltd & Co Kg Acoustic liner and gas turbine engine with such acoustic liner
US11566564B2 (en) 2020-07-08 2023-01-31 Raytheon Technologies Corporation Acoustically treated panels
US11230928B1 (en) 2020-07-22 2022-01-25 Raytheon Technologies Corporation Guide vane with truss structure and honeycomb
US11512608B2 (en) 2020-08-14 2022-11-29 Raytheon Technologies Corporation Passive transpirational flow acoustically lined guide vane
US11408349B2 (en) * 2020-08-14 2022-08-09 Raytheon Technologies Corporation Active flow control transpirational flow acoustically lined guide vane
US20220049656A1 (en) * 2020-08-14 2022-02-17 Raytheon Technologies Corporation Active flow control transpirational flow acoustically lined guide vane
US11804206B2 (en) 2021-05-12 2023-10-31 Goodrich Corporation Acoustic panel for noise attenuation
US12104536B2 (en) 2021-05-12 2024-10-01 Rohr, Inc. Nacelle liner comprising unit cell resonator networks
US12118971B2 (en) 2021-05-12 2024-10-15 B/E Aerospace, Inc. Aircraft acoustic panel
US11830467B2 (en) 2021-10-16 2023-11-28 Rtx Coroporation Unit cell resonator networks for turbomachinery bypass flow structures
US11781485B2 (en) 2021-11-24 2023-10-10 Rtx Corporation Unit cell resonator networks for gas turbine combustor tone damping
US12085023B2 (en) 2022-10-03 2024-09-10 General Electric Company Circumferentially varying fan casing treatments for reducing fan noise effects
US12092034B2 (en) 2022-10-03 2024-09-17 General Electric Company Circumferentially varying fan casing treatments for reducing fan noise effects
US12435671B2 (en) 2022-10-03 2025-10-07 General Electric Company Circumferentially varying fan casing treatments for reducing fan noise effects
US20250052163A1 (en) * 2023-08-09 2025-02-13 General Electric Company Turbofan engine including integrated pylon and fan outlet guide vane with noise reduction features
US12228053B1 (en) * 2023-08-09 2025-02-18 General Electric Company Turbofan engine including integrated pylon and fan outlet guide vane with noise reduction features

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