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
  • F02C7/04—Air intakes for gas-turbine plants or jet-propulsion plants
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B64—AIRCRAFT; AVIATION; COSMONAUTICS
  • B64D—EQUIPMENT FOR FITTING IN OR TO AIRCRAFT; FLIGHT SUITS; PARACHUTES; ARRANGEMENT OR MOUNTING OF POWER PLANTS OR PROPULSION TRANSMISSIONS IN AIRCRAFT
  • B64D33/00—Arrangements in aircraft of power plant parts or auxiliaries not otherwise provided for
  • B64D33/02—Arrangements in aircraft of power plant parts or auxiliaries not otherwise provided for of combustion air intakes
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B64—AIRCRAFT; AVIATION; COSMONAUTICS
  • B64D—EQUIPMENT FOR FITTING IN OR TO AIRCRAFT; FLIGHT SUITS; PARACHUTES; ARRANGEMENT OR MOUNTING OF POWER PLANTS OR PROPULSION TRANSMISSIONS IN AIRCRAFT
  • B64D33/00—Arrangements in aircraft of power plant parts or auxiliaries not otherwise provided for
  • B64D33/02—Arrangements in aircraft of power plant parts or auxiliaries not otherwise provided for of combustion air intakes
  • B64D2033/0226—Arrangements in aircraft of power plant parts or auxiliaries not otherwise provided for of combustion air intakes comprising boundary layer control means
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B64—AIRCRAFT; AVIATION; COSMONAUTICS
  • B64D—EQUIPMENT FOR FITTING IN OR TO AIRCRAFT; FLIGHT SUITS; PARACHUTES; ARRANGEMENT OR MOUNTING OF POWER PLANTS OR PROPULSION TRANSMISSIONS IN AIRCRAFT
  • B64D33/00—Arrangements in aircraft of power plant parts or auxiliaries not otherwise provided for
  • B64D33/02—Arrangements in aircraft of power plant parts or auxiliaries not otherwise provided for of combustion air intakes
  • B64D2033/0266—Arrangements in aircraft of power plant parts or auxiliaries not otherwise provided for of combustion air intakes specially adapted for particular type of power plants
  • B64D2033/0286—Arrangements in aircraft of power plant parts or auxiliaries not otherwise provided for of combustion air intakes specially adapted for particular type of power plants for turbofan engines
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T137/00—Fluid handling
  • Y10T137/0536—Highspeed fluid intake means [e.g., jet engine intake]

Definitions

• the present invention relates to an air intake structure for a turbojet nacelle adapted to channel an air flow to a fan of the turbojet engine.
• An aircraft is propelled by one or more propulsion units comprising a turbojet engine housed in a tubular nacelle.
• Each propulsion unit is attached to the aircraft by a mast located generally under a wing or at the fuselage.
• a nacelle generally has a structure comprising an air inlet upstream of the engine, a median section intended to surround a fan of the turbojet, a downstream section housing thrust reverser means and intended to surround the combustion chamber of the turbojet engine, and is generally terminated by an ejection nozzle whose outlet is located downstream of the turbojet engine.
• the air intake comprises, on the one hand, an inlet lip adapted to allow optimal capture to the turbojet of the air necessary to supply the blower and the internal compressors of the turbojet engine, and other on the other hand, a downstream structure to which the lip is attached and intended to properly channel the air towards the blades of the fan.
• the assembly is attached upstream of a fan casing belonging to the median section of the nacelle.
• the air intake structure generally has a substantially annular downstream structure comprising an outer surface providing external aerodynamic continuity of the nacelle and an inner surface ensuring the aerodynamic continuity of the nacelle internal.
• the air intake lip ensures the upstream junction between these two walls.
• An air intake lip structure can include many components and house various equipment, such as deicing equipment, for example.
• various equipment such as deicing equipment, for example.
• the junctions between the different walls and elements alike reduce the structure and negatively affect the aerodynamic performance.
• laminar nacelles with an air intake structure have been developed with external continuity improving the aerodynamic performance.
• Such a structure is described in particular in document FR 2 906 568. Thanks to the fact that, in such an air inlet, the lip is in fact integrated into the outer wall, the junctions between these members are eliminated which may adversely affect the aerodynamic performance of the nacelle.
• LFC Longminar Forward Cowl
• This fixed ferrule is generally equipped with acoustic attenuation means.
• a disadvantage of this type of air intake lies in the junction zone between the inner edge of the lip and the upstream edge of the inner fixed wall, which zone is likely to undergo axial displacements or even to open in certain engine operating configurations.
• the integral and mobile outer wall remains heavy and tends to move under load. To prevent these movements, the air inlet must be equipped with reinforcement means, which increases the mass, and is therefore not desirable.
• This detachment has the effect of degrading the aerodynamic performance of the inner face of the air intake, and lead to leakage defects likely to longevity and the proper functioning of the organs (electrical, hydraulic, pneumatic) Certainly located inside the air intake.
• the thickness of the air intake lip remains relatively high in this type of structure, in particular to contribute to a good mechanical strength of the assembly, which limits the implementation of electric deicing devices by heating resistors.
• the implementation of such defrosting devices being essential for such an air intake, which is, because of its structure, hardly compatible with the usual hot air pneumatic solutions. There is therefore a need to reduce the deformation and mass of this type of structure.
• the present invention is intended in particular to remedy these drawbacks and consists for this purpose of an air intake structure for a turbojet engine nacelle comprising, on the one hand, at least one fixed inner wall intended to be attached to at least one an element of a median section of the nacelle, and secondly, at least one longitudinal outer wall extended by an air inlet lip connected to the fixed inner wall, characterized in that at least the portion forming air inlet lip is equipped with means for depressurizing at least a portion of the lip.
• this may result from air flows surrounding the air intake lip. Indeed, the air flowing at a high speed around the nacelle, the air pressure at the air inlet lip is low, the air present being rapidly sucked downstream of the nacelle .
• the present invention by depressurizing the air intake lip, makes it possible to generate suction forces internal to the lip which balance the deformation forces towards the before and thus counterbalance the deformations undergone by the air intake lip.
• the air intake lip is equipped with at least one partition defining with the air intake lip at least one air inlet lip compartment, said compartment being associated with the means for setting air. depression.
• the partition may comprise at least one acoustic panel.
• the vacuum means comprise at least one pump, including electric.
• the pump has a suction outlet opening downstream of the air inlet lip, in particular for example, in the outer wall, in the inner wall, downstream of the fan.
• the vacuum means comprise at least one opening in the outer wall.
• the openings are formed in the wall of the lip near the fixed inner wall.
• At least a portion of the openings are disposed along a substantially peripheral line of the air intake lip.
• the openings comprise substantially round openings.
• the openings comprise oblong openings, the major axis of the oblong opening being preferentially oriented along a peripheral line to the air inlet.
• the openings comprise openings in the form of open serrations at a line of contact of the outer wall with the inner wall and thus allowing a limitation of the contact surface between the lip air inlet and the fixed wall.
• the longitudinal outer wall is removable.
• the longitudinal outer wall is mounted translatable.
• the element of the median section of the nacelle is a fan casing.
• the air intake lip is integrated with the outer wall.
• the internal wall is equipped with acoustic attenuation means.
• the present invention also relates, of course, to a turbojet engine nacelle comprising such an air intake structure.
• FIG. 1 is a longitudinal sectional view of an air intake structure for a turbojet engine nacelle according to the prior art
• FIG. 2 is a diagrammatic representation in section of the forces exerted on the air intake lip of the structure of FIG. 1,
• FIG. 3 is a diagrammatic representation in section of an air intake structure according to the invention having means for depressurizing the air intake lip,
• FIGS. 4 to 6 are diagrammatic representations of various embodiments of openings for the depression of the air inlet of FIG. 3;
• FIG. 7 represents an alternative embodiment of the invention.
• a nacelle generally has a substantially tubular structure comprising an air inlet upstream of the engine (FIG. 1), a median section intended to surround a fan of the turbojet engine, a downstream section housing a thrust reverser means and intended to surround the engine. combustion chamber of the turbojet, and is generally terminated by an ejection nozzle whose outlet is located downstream of the turbojet engine.
• Figure 1 shows a longitudinal sectional view of an air inlet structure 1 according to the prior art.
• This air intake structure 1 is located upstream of the median section 2 of the nacelle and comprises, on the one hand, an air intake lip 3 adapted to allow optimal capture to the turbojet of the air necessary for its supply, and secondly, a downstream structure 4 on which is reported the lip and intended to properly channel the air to the blades of the fan.
• the air intake structure 1 generally has a substantially annular downstream structure 4 comprising an outer wall 40 providing external aerodynamic continuity of the nacelle and an inner wall 41 ensuring the internal aerodynamic continuity of the nacelle.
• the air intake lip 3 ensures the upstream connection between these two walls 40, 41.
• the inner wall 41 is generally attached to a fan casing 20 belonging to the central section 2 and with which it constitutes a fixed structure.
• the outer wall 40 is in turn generally attached to an outer wall 21 of the median section with which it provides external aerodynamic continuity.
• the air inlet lip 3 is generally separated from the downstream part 40 of the air inlet structure 1 by a partition 5 contributing to the holding of the assembly and defining with the lip 3 a compartment 3a inside said lip 3.
• the outer wall 40 can be attached removably to allow access to the interior of the air inlet structure 1, in particular to access internal equipment such as a defrosting system. the air inlet 1 and the lip 3.
• the air intake lip 3 is an integral part of the outer wall 40 which it extends to form a single panel generally mounted translatable towards the front of the nacelle.
• the air intake lip 3 undergoes forward pressure loading (arrow) which tends to deform the inlet lip of therefore possess a certain mechanical strength, generally by providing a sufficient lip thickness 3.
• the wall 5 is fixed rigidly at 51 with the internal wall 41.
• this junction is preferably by a seal only. If the outer wall 40 opens, this junction is then rigid, for example by means of fasteners.
• these pressure loading forces are compensated by depression of the air inlet lip 3 and more particularly of the compartment 3a if necessary.
• FIG. 4 A first exemplary implementation of the invention is shown in FIG. 4.
• an air inlet structure 100 substantially similar to the air inlet structure 1, is equipped with depression means of the compartment 3a of the air intake lip 3 is having in the form of openings 30 formed in the wall of the air inlet lip.
• these openings 30 are located on an inner face of the air inlet structure, close to the inner wall 41 and its junction with said air inlet lip 3.
• the openings 30 are arranged along a substantially peripheral line of the air inlet structure.
• FIGS. 4 to 6 show different embodiments of the openings 30 enabling the compartment 3a of the air inlet lip 3 to be depressed.
• the openings 30 may in particular be circular ( Figure 4) or oblong ( Figure 5).
• They can also be made at a line of contact and support between the air intake lip 3 and the inner wall 41, in particular in the form of serrations made in this line of contact.
• FIG. 7 presents a third embodiment of the invention.
• FIG. 7 shows an air intake structure 200 which differs from the air intake structure 100 in that the means of depression of the inlet lip compartment 3a of FIG. a pump 60, electrically heated, having a suction duct 61 opening into the air inlet lip compartment 3a and a suction duct 62 of the sucked air. opens in a downstream part of the air inlet 200. It can be provided that this conduit 62 opens, for example, into the outer wall 40, into the inner wall 41 near the fan, or further downstream after the blower and the compressor.

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

Applications Claiming Priority (2)

Publications (1)

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Family Applications (1)

Country Status (8)

Families Citing this family (2)

Family Cites Families (18)

• 2011
  • 2011-06-01 FR FR1154810A patent/FR2975972B1/fr not_active Expired - Fee Related
• 2012
  • 2012-05-11 EP EP12728657.3A patent/EP2714519A1/fr not_active Withdrawn
  • 2012-05-11 RU RU2013157745/11A patent/RU2013157745A/ru not_active Application Discontinuation
  • 2012-05-11 BR BR112013027562A patent/BR112013027562A2/pt not_active IP Right Cessation
  • 2012-05-11 WO PCT/FR2012/051046 patent/WO2012164187A1/fr active Application Filing
  • 2012-05-11 CA CA 2837605 patent/CA2837605A1/fr not_active Abandoned
  • 2012-05-11 CN CN201280024936.7A patent/CN103562068B/zh not_active Expired - Fee Related
• 2013
  • 2013-12-02 US US14/093,903 patent/US20140130889A1/en not_active Abandoned

Non-Patent Citations (1)

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