Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02K—JET-PROPULSION PLANTS
  • F02K1/00—Plants characterised by the form or arrangement of the jet pipe or nozzle; Jet pipes or nozzles peculiar thereto
  • F02K1/54—Nozzles having means for reversing jet thrust
  • F02K1/64—Reversing fan flow
  • F02K1/70—Reversing fan flow using thrust reverser flaps or doors mounted on the fan housing
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02K—JET-PROPULSION PLANTS
  • F02K1/00—Plants characterised by the form or arrangement of the jet pipe or nozzle; Jet pipes or nozzles peculiar thereto
  • F02K1/54—Nozzles having means for reversing jet thrust
  • F02K1/64—Reversing fan flow
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02K—JET-PROPULSION PLANTS
  • F02K1/00—Plants characterised by the form or arrangement of the jet pipe or nozzle; Jet pipes or nozzles peculiar thereto
  • F02K1/54—Nozzles having means for reversing jet thrust
  • F02K1/64—Reversing fan flow
  • F02K1/70—Reversing fan flow using thrust reverser flaps or doors mounted on the fan housing
  • F02K1/72—Reversing fan flow using thrust reverser flaps or doors mounted on the fan housing the aft end of the fan housing being movable to uncover openings in the fan housing for the reversed flow
• • 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
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
  • Y02T50/00—Aeronautics or air transport
  • Y02T50/60—Efficient propulsion technologies, e.g. for aircraft

Definitions

• the present invention relates to a propulsion unit for aircraft, provided with thrust reversal means.
• Prior art known propellant sets of the type comprising a nacelle and inside this nacelle, a turbojet engine.
• turbojet engine is a double flow: a "primary” or “hot” flow of it flowing inside the engine of the turbojet, and a flow called “secondary” or “cold” circulating on the periphery of this engine, in a vein delimited on the one hand by the outer casing of this engine, and on the other hand by the inner wall of the nacelle.
• the thrust of the turbojet is mainly ensured by the secondary flow.
• an effective means of braking the aircraft on landing is to deflect forward of the aircraft at least a portion of this secondary flow: it uses for this so-called inversion means of thrust, well known in itself.
• these thrust reversal means which are of the door type (opening of doors swinging towards the outside of the nacelle making it possible to fold the secondary flow forward) or grids (sliding of panels discovering forward flow deflection grates forward), are located downstream of the turbojet fan housing, in a portion of the nacelle specifically designed to incorporate these inversion means.
• This specific part of the nacelle has a significant weight because of all the fixed and mobile thrust reversing members that it incorporates, and it necessarily induces an overall length of nacelle important.
• the present invention is intended in particular to eliminate these disadvantages.
• a propulsion unit of the type comprising a nacelle and, inside this nacelle, a turbojet engine.
• double flow comprising itself a fan casing in which are located a fan and a set of flow rectification blades, this propulsion unit being remarkable in that it comprises thrust reversing means located between said fan and said set of blades.
• said thrust reverser means comprise a plurality of windows formed in said fan casing, between said fan and said rectifying vanes, and means for returning the secondary air flow towards the outside and towards the front of the nacelle, through said windows;
• said means for returning the secondary air flow comprise said flow rectification vanes, movable between a normal operating position in which they allow the passage of secondary air flows, and a thrust reversal position in which they prevent this passage;
• said flow rectification vanes are each pivotally mounted about a substantially radial axis
• said means for returning the secondary air flow further comprise a plurality of deflection grids of the secondary air flow distributed between said fan casing and the outer skin of said nacelle, facing said windows, and movable inner panels; between a normal operating position, in which they provide aerodynamic continuity along said housing, and a thrust reversal position, in which they allow the flow of air to flow through said deflection grids;
• said inner panels are slidably mounted on said casing between a position where they close said windows, and a position where they release these windows: this sliding operation of the interior panels is very simple and is compatible with the space available between the casing of the casing; blower and the outer skin of the basket;
• said means for returning the secondary air flow comprise thrust reversal flaps, pivotally mounted on said fan casing upstream of said straightening vanes, between a position of normal operation in which they allow the passage of secondary air flow and seal said windows, and a reverse thrust position in which they prevent this passage and release said windows;
• said means for returning the secondary air flow comprise outer panels positioned opposite said windows, pivotally mounted on the outer skin of the nacelle 1'acit between a substantially tangential closing position, and a substantially radial position; opening: these outer panels thus work in the manner of the slats of a shutter, and their operation in concert can be achieved in a very simple manner, for example by a rotating annular ring;
• the outer panels are adapted to ensure the diversion of the secondary air flow: in this way it is possible to dispense with deflection grids separated from these outer panels, which is extremely advantageous in terms of weight and simplification of the structure; note that it is also possible to consider associating with these outer panels any other means of deflecting the secondary air flow, such as deflectors suitably shaped cou plés mechanically to or sol idaires of these panels exterieur;
• said means for returning the secondary air flow comprise doors arranged upstream of said straightening vanes, able to pivot towards the outside of the nacelle.
• the figure represents in perspective the outside of the upstream part of a propulsion unit according to the invention, in flight configuration (direct jet),
• FIG. 2 represents in perspective the interior of this upstream part, the fan having been removed
• FIG. 3 similar to FIG. 1, represents this upstream portion in thrust reversal configuration
• FIG. 4 represents, in perspective, a detailed view of zone III of the assembly represented in FIG. 3;
• FIG. 5 similar to FIGS. 1 and 3, represents said assembly after removal of its outer skin
• FIG. 6 represents this same assembly after removal of the thrust reversal grids
• FIG. 7 represents a detailed view of zone VII of FIG. 6, corresponding to a thrust reversal configuration
• FIG. 8 which is a detailed view of the zone VIII of FIG. 9, shows the flux-straightening vanes of the aforementioned assembly, being rotated towards their closed position
• FIG. 9 is a perspective view taken from the rear of the aforementioned assembly, the flux rectification blades being represented in the closed position
• FIG. 10 is an axial sectional view of the detail zone X of the assembly of FIG. 1, this assembly being in the configuration of thrust reversal,
• FIG. 11 similar to FIG. 6, represents another embodiment of an assembly according to the invention, in flight configuration (direct jet),
• FIG. 12 is a front view of the assembly of FIG.
• FIGS. 13 and 14 are views similar to those of FIGS. 11 and 12, (1 so that it has been removed to facilitate expl ications), the assembly being represented in a thrust reversal configuration, and
• Figure 15 is a view similar to that of Figure 4, showing another possible arrangement of the outer panels disposed on the outer skin of the nacelle.
• the d irections conventionally represent the longitudinal directions, transverse and vertical aircraft to which the propulsion unit to be described is intended to be associated.
• FIG. 1 shows the upstream portion of a propulsion assembly according to the invention.
• This upstream part comprises an air inlet 1 provided with an air inlet lip 3 intended to channel the outside air to the motor (not shown) of the propulsion unit according to the invention.
• the air intake lip 3 On its outer face, the air intake lip 3 is extended downstream by an external air inlet 5, and on its underside, typically, by an acoustic absorption structure 7, such as a honeycomb structure.
• the outer skin 5 of the air intake 1 is extended downstream by a fan cowl 9 provided with an annular opening 11 between the two edges of which is mounted a set of outer panels 13, each pivoting around an axis between a closed position visible in Figures 1 and 2, and an open position visible in Figures 3 and 4.
• the acoustic absorption elements 7 are extended downstream by a fan casing 10, a kind of cylindrical shell inside which is rotatably mounted the engine fan (this blower having been removed in Figure 2, for ease of explanation).
• any deflection gratings 17 are arranged substantially evenly over the entire periphery of the fan casing. 9.
• Each of the deflection grids 1 7 comprises slats 1 9 oriented so as to be able to send outwards and towards the front of the air inlet 1, the so-called secondary air flow pushed by the blower and circulating in a substantially annular air flow d isposée around the moteu r (not shown) of the turbojet engine of the propulsion unit according to the invention.
• any deflection grids 17 are arranged upstream of the flow straightening vanes 15.
• each panel 21 is located under a possible respective deflection grid 17.
• each panel 21 slides towards the front of the fan casing 10, by means of appropriate rails / rails, so as to reach the position shown in FIG. 7, in which the windows 23 located under each possible deflection grid 17 are released.
• each inner panel 21 is represented by the line 25 of FIG. 7: this stroke can be obtained by means of rails disposed on fixed members 27 separating the windows 23 from each other.
• the position of the rails is indicative and may for example be used to ensure the closure of the front zone between the secondary flow stream of air and the outer skin of the nacelle.
• each blade 15 can therefore, by pivoting about a substantially radial axis associated with A, pass from a normal operating position, in which these blades allow the passage of the secondary air flow stirred by the fan, to a closed position, visible in Figure 9, wherein these blades 15 are substantially contiguous, and thus prevent the passage of said secondary air flow.
• the inner panels 21 are in the closed position shown in FIG.
• the air blown by the blower passes through the flow rectification vanes 15, joins the air operating duct, and is ejected downstream of the propulsion unit. according to the invention, thus allowing the propulsion of the aircraft (so-called "direct jet” configuration).
• the closure of the outer panels 1 3 ensures the aerodynamic continuity of the fan cowl 9, and the closure of the inner panels 21 ensures aerodynamic continuity within the fan casing 10.
• outer panels 13 and the inner panels 21 are placed in the open position, as shown in FIGS. 3, 4 and 10.
• the flow straightening vanes 15 are also placed in their closed position, as can be seen in FIG. 9.
• the propulsion unit which has just been described makes it possible to deport the thrust reverser device upstream of the flow straightening vanes, which makes it possible to To be free from a conventional inversion device disposed downstream of these, it is possible in this way to significantly reduce the longitudinal encom- beration of the propulsion unit and to obtain a considerable weight gain.
• the distribution of the thrust reversal system over the entire periphery of the propulsion unit makes it possible to obtain a remarkable balancing of the forces involved during the phases of thrust reversal, thereby guaranteeing less fatigue for the assembly. parts concerned.
• the present invention is only limited to the example described and shown, provided for illustrative purposes only.
• the flow straightening vanes 15 can be fixed, and the blocking of the secondary air flow is done by flaps 30 (see FIGS. 1 1, 1 4 and 1 5) positioned upstream of these blades, and articulated on the fan casing 10 between a flight position ("direct jet") in which they close the windows 23 (see Figures 1 1, 1 2 and 1 3), and a thrust reversal position in which they plug the secondary air stream (see Figures 14 and 15).

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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)

Applications Claiming Priority (2)

Publications (1)

Family

ID=43086911

Family Applications (1)

Country Status (8)

Families Citing this family (14)

Family Cites Families (11)

• 2010
  • 2010-04-09 FR FR1052689A patent/FR2958688B1/fr not_active Expired - Fee Related
• 2011
  • 2011-03-10 CN CN2011800138798A patent/CN102792001A/zh active Pending
  • 2011-03-10 US US13/640,070 patent/US9133790B2/en not_active Expired - Fee Related
  • 2011-03-10 EP EP11712982A patent/EP2556237A1/de not_active Withdrawn
  • 2011-03-10 CA CA 2792288 patent/CA2792288A1/fr not_active Abandoned
  • 2011-03-10 WO PCT/FR2011/050483 patent/WO2011124793A1/fr active Application Filing
  • 2011-03-10 BR BR112012022437A patent/BR112012022437A2/pt not_active IP Right Cessation
  • 2011-03-10 RU RU2012146860/06A patent/RU2012146860A/ru not_active Application Discontinuation

Non-Patent Citations (1)

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