Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
  • F04D—NON-POSITIVE-DISPLACEMENT PUMPS
  • F04D29/00—Details, component parts, or accessories
  • F04D29/26—Rotors specially for elastic fluids
  • F04D29/32—Rotors specially for elastic fluids for axial flow pumps
  • F04D29/325—Rotors specially for elastic fluids for axial flow pumps for axial flow fans
  • F04D29/329—Details of the hub
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B64—AIRCRAFT; AVIATION; COSMONAUTICS
  • B64C—AEROPLANES; HELICOPTERS
  • B64C11/00—Propellers, e.g. of ducted type; Features common to propellers and rotors for rotorcraft
  • B64C11/02—Hub construction
  • B64C11/04—Blade mountings
  • B64C11/06—Blade mountings for variable-pitch blades
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B64—AIRCRAFT; AVIATION; COSMONAUTICS
  • B64C—AEROPLANES; HELICOPTERS
  • B64C11/00—Propellers, e.g. of ducted type; Features common to propellers and rotors for rotorcraft
  • B64C11/46—Arrangements of, or constructional features peculiar to, multiple propellers
  • B64C11/48—Units of two or more coaxial propellers
• • 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
  • B64D27/00—Arrangement or mounting of power plants in aircraft; Aircraft characterised by the type or position of power plants
  • B64D27/02—Aircraft characterised by the type or position of power plants
  • B64D27/026—Aircraft characterised by the type or position of power plants comprising different types of power plants, e.g. combination of a piston engine and a gas-turbine
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
  • F04D—NON-POSITIVE-DISPLACEMENT PUMPS
  • F04D29/00—Details, component parts, or accessories
  • F04D29/26—Rotors specially for elastic fluids
  • F04D29/32—Rotors specially for elastic fluids for axial flow pumps
  • F04D29/321—Rotors specially for elastic fluids for axial flow pumps for axial flow compressors
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
  • F04D—NON-POSITIVE-DISPLACEMENT PUMPS
  • F04D29/00—Details, component parts, or accessories
  • F04D29/26—Rotors specially for elastic fluids
  • F04D29/32—Rotors specially for elastic fluids for axial flow pumps
  • F04D29/321—Rotors specially for elastic fluids for axial flow pumps for axial flow compressors
  • F04D29/322—Blade mountings
  • F04D29/323—Blade mountings adjustable
• • 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 propeller hub with variable pitch blades for a turbomachine type unvented fan (in English "open rotor” or “unducted fan”).
• the blower of a turbomachine of this type typically comprises two coaxial and contra-rotating external propellers, respectively upstream and downstream, which are each driven in rotation by a turbine of the turbomachine and which extend substantially radially outwardly of the engine nacelle. this turbomachine.
• Each propeller usually comprises a hub of the type comprising a polygonal support ring of said blades, concentric with the longitudinal axis of the turbomachine and composed of two annular end flanks spaced parallel to one another and between which are diametrically secured , by rooting zones coming from the annular flanks, rings with radial cylindrical housings for receiving said blades.
• the rings are equi-angularly distributed at the lateral periphery of the polygonal ring and separated from each other by intermediate flat areas with recesses (or openings) therethrough, and a connecting means connects the polygonal ring to a rotor element of turbine of the turbomachine.
• the blades can rotate in the housings of the rings of the polygonal ring and are rotated around the axes of the blades by appropriate means so as to adjust the angular setting of the blades, and to optimize it according to the conditions of the blades. operation of the turbomachine.
• the rotating parts of the turbomachine and in particular the hub and the blades of the propeller, are subjected, in varying degrees, to significant constraints, be they mechanical, thermal, aerodynamic, etc. ..
• the cylindrical housings blades tend to deform under the significant forces exerted at the level of the radial rings of the polygonal ring, to take an oval configuration.
• the rooting or connecting zones of the rings on the annular flanks are wide and extend over a large peripheral portion of the rings for reasons of mechanical strength and rigidity, the tensile forces exerted by these flanks on the rings cause ovalization thereof.
• the rolling tracks of the bearings which are provided between the cylindrical housing of each ring and a rotary device (including plate and ring) bearing the blade and to vary the setting thereof, may deteriorate rapidly until it can no longer guarantee the correct operation of the blades, with the consequences that this may entail.
• the intermediate zones of the lateral periphery of the ring are provided with through recesses formed alternately and consecutively between the radial receiving housing rings. blades. In this way, the mass gain is significant without thereby adversely affecting the mechanical characteristics of the polygonal ring.
• the blade roots connected to the outer side of the polygonal ring, as opposed to its inner side facing the turbines, are subjected to relatively high temperatures due in particular to the circulation of the hot air of the ventilation circuits of the turbine elements. Indeed, a portion of this hot air passes through the recesses of the intermediate zones of the polygonal ring and circulates around the feet of the blades by heating them.
• the composite materials of the blades are incompatible with these temperatures.
• the combustion gases passing coaxially through the turbomachine participate in maintaining these high temperature levels including conduction through the parts themselves, despite the presence of ventilation circuits.
• the object of the present invention is to remedy these drawbacks and concerns a propeller hub with variable pitch blades whose design of said polygonal ring notably guarantees the absence of deformation of the cylindrical housings of the rings.
• the propeller hub with variable pitch blades for a longitudinal axis turbomachine of the type comprising:
• a polygonal ring for supporting the blades, concentric with the longitudinal axis and composed of two annular end flanks spaced parallel to one another and between which are diametrically secured, by rooting zones issuing from said annular flanks radial-cylindrical housing rings for receiving the blades, said rings being equiangularly distributed at the lateral periphery of the polygonal ring and separated from each other by intermediate zones with through recesses, and
• the intermediate zones defined between two consecutive rings and the end annular flanks comprise reinforcing elements of the rings, which are arranged radially and / or tangentially and integral at least with the walls side of the two consecutive rings.
• the reinforcing elements when they are arranged radially, substantially parallel to said end annular flanks, are each in the form of a rigid thin plate, arranged radially in the through recess of the intermediate portion. and secured, by its lateral edges, corresponding side walls of the two consecutive rings.
• the radial plate reinforcing elements constitute stiffening ribs which, by virtue of their arrangement between two consecutive rings, perpendicular to the diametrical connection thereof to the end annular flanks by the zones d rooting, prevent the ovalization of said rings and, therefore, that of radial cylindrical housings due to the stresses exerted. These are therefore taken without deformation of the rings.
• the rolling tracks of the bearings provided on the rotary devices of the blades retain their integrity.
• said rooting zones of the annular end flanks on the rings may have a reduced thickness due to the presence of said reinforcing elements.
• the thickness of the rooting zones is substantially of the order of that of said reinforcing elements or that of said rings.
• the plate reinforcing elements of the rings are situated in the radial median plane of said polygonal ring, perpendicular to the longitudinal axis and containing the geometric axes of the cylindrical radial receiving housings of the blades, and equidistant from the two annular flanks end of said ring.
• each ring is held rigidly by four links perpendicular to each other (two with the rooting zones of the end annular flanks, two with the reinforcing elements of the rings), conferring on each of the rings a satisfactory rigidity. All of the reinforcing elements thus form a ring stiffening discs preventing ovalization of their housing.
• said plate reinforcing elements extend radially over the entire height of said rings. In this way, the objective of minimizing the deformation of the housing rings and strengthen their resistance to operating forces is achieved.
• the reinforcing elements close off the through recesses of the intermediate zones defined between said consecutive rings and said end annular flanks, said lateral periphery of said polygonal ring being substantially solid and continuous.
• the ventilation circuits are channeled and confined on the inner side of the polygonal ring and thus circulating downstream of the turbomachine, without crossing the latter. In this way, it is safe to use blades with composite feet for their many advantages and avoid the deterioration of the feet.
• the tangential reinforcement elements are each in the form of a web of thin material, all of said webs closing said lateral periphery of said polygonal ring.
• said thin webs are located substantially in the middle of the thickness of the polygonal ring.
• said rooting zones coming from the annular end flanks and diametrically connecting the rings have a thickness scaled down.
• the reduced thickness of these zones corresponds for example substantially to that of the rings.
• each reinforcing element is in the form of two rigid thin plates, perpendicular to each other by defining a transverse cross section, one of the plates being arranged radially in the recess passing by connecting the two corresponding rings, and the other perpendicular plate being arranged tangentially at the lateral periphery of the polygonal ring by connecting the annular end flanks of the polygonal ring to thereby close the through recess.
• the reinforcing elements are integrated in the polygonal ring.
• the whole of it is thus obtained directly, in one piece, by rolling and machining techniques.
• said reinforcing elements can also be fixedly attached to the polygonal ring, after obtaining it.
• the invention also relates to a turbomachine of the non-ducted fan type.
• a turbomachine of the non-ducted fan type comprises a propeller hub of said fan, as defined above.
• FIG. 1 is a schematic longitudinal sectional view of a turbomachine of the unfired propeller type.
• FIG. 2 shows a partial perspective view of the upstream propeller of said turbomachine, with its polygonal hub ring carrying the blades of the propeller and equipped with radial reinforcing elements.
• Fig. 3 is a partial enlarged view of the polygonal ring of Fig. 2 showing the thin plate radial reinforcing elements for the blade support rings.
• FIG. 4 is a cross section along the plane AA of Figure 3 of the reinforcing element.
• FIG. 5 shows a partial perspective view of the upstream propeller of the turbomachine, with its polygonal hub ring carrying the blades of the propeller and equipped with tangential reinforcing elements.
• FIG. 6 is a partial enlarged view of the hub ring of FIG. 5, without the corresponding blades and showing the tangential tangs reinforcing element, connecting the rings with receiving housings of the blades.
• FIG. 7 is a radial section of said polygonal ring along the plane A-A of FIG. 6.
• Figure 8 shows, in cross section similar to Figure 4, an alternative embodiment of said reinforcement element both radial and tangential.
• FIG. 1 shows a turbomachine 1 with a non-ducted fan (in English “open rotor” or “unducted fan”) which comprises from upstream to downstream, in the direction of flow of gases at the same time.
• a non-ducted fan in English "open rotor” or “unducted fan”
• a compressor 2 inside the turbomachine of longitudinal axis A, a compressor 2, an annular combustion chamber 3, a high-pressure turbine 4, and two low-pressure turbines 5, 6 which are counter-rotating, that is to say they rotate in two opposite directions about the longitudinal axis A of the turbomachine.
• Each of these downstream turbines 5, 6 is integral in rotation with an external helix 7, 8 extending radially outside the nacelle 10 of the turbomachine, this nacelle 10 being substantially cylindrical and extending along the length axis A around the compressor 2, the combustion chamber 3, and the turbines 4, 5 and 6.
• the flow of air 1 1 which enters the turbomachine is compressed then is mixed with fuel and burned in the combustion chamber 3, the combustion gases then passing into the turbines to drive in rotation the propellers 7.8 which provide the most of the thrust generated by the turbomachine.
• the combustion gases leaving the turbines are expelled through a nozzle 12 (arrows 14) to increase the thrust.
• the propellers 7, 8 are arranged coaxially one behind the other and comprise a plurality of blades 15 regularly distributed around the longitudinal axis A of the turbomachine 1. These blades 15 extend substantially radially and are of the variable-pitch type, that is to say that they can rotate about their axes so as to optimize their angular position as a function of the operating conditions of the turbomachine.
• each propeller 7, 8 comprises a rotary hub or rotor element 16 formed mainly by a polygonal ring 17 supporting the blades 15 and arranged concentrically with the rotor. longitudinal axis A of the turbomachine 1, perpendicular to the latter.
• the polygonal ring 17 of the hub 16 is in the corresponding rotating part 10A of the nacelle 10 and is connected thereto by a suitable connecting means symbolized at 18 in Figure 1.
• This polygonal ring 17 for supporting the blades 15 is generally structurally monobloc and its lateral periphery 19 is composed of two polygonal end annular flanks (or portions) 20 and 21 parallel to each other and connected to one another by portions cylindrical intermediates 22, such as radial rings (or drums) 23. These are arranged equi-angularly distributed at the lateral periphery thus formed 19 of the ring 17 and the side walls 25 of the rings define radial cylindrical housings 24 whose axes B converge in the same radial plane towards the longitudinal axis A of the turbomachine 1, and which are intended to receive mounting devices 29 blades.
• each device 29 carries, on one side, the foot 15A of the blade 15, while it engages, on the other side, in the housing 24 of the ring 23.
• Bearings not shown, provided in the housing provide rotation, by appropriate means not illustrated, of the mounting device relative to the housing of the ring.
• the lateral walls 25 of the cylindrical rings 23 are integral with the end annular flanks 20, 21 by rooting or connecting zones 30 provided in diametrical opposition on the periphery. 19 of the polygonal ring 17 and having a height preferably identical to that of the annular end flanks.
• the receiving housings 24 of the mounting devices 29 of the blades 15 are situated at the vertices of intersection of the planar zones 31 (twelve in this example) of the polygonal lateral periphery 19 the ring which is carried out in one piece including by rolling techniques and suitable machining.
• the planar zones 31, intermediate between two consecutive rings are provided with through recesses or openings 33 which are delimited by the side walls 25 of the consecutive rings and by the portions. corresponding annular end flanks 20, 21 of the ring.
• These recesses 33 are thus alternated with the rings 23 at the lateral periphery 19 of the polygonal ring forming the hub 16 of the propeller.
• two of these through recesses 33, as currently made, are shown in detail D of FIG. 2, with the rooting zones 30 (one is only visible) diametrically fastening the ring 23 to the annular flanks 20, 21 . It can be seen that the thickness or width of the zone represented is important, leading, as previously mentioned, to ovalization of the ring because of the tensile forces exerted by the flanks thereon.
• reinforcing elements 26 are provided in the through recesses 33 to prevent deformation of the rings 23 and, in particular, their ovalization due to the intense forces exerted on them.
• the reinforcing elements 26 are arranged radially and are rigidly associated with the side walls 25 of two consecutive rings 23 by acting on these sidewalls perpendicularly to the diametric rooting zones 30 of the rings 25 with the annular flanks. end 20, 21 of the ring, that is to say where the risk of ovality is important.
• the other zones 30 of the ring have a reduced thickness e (FIG.
• the reinforcing elements 26 are defined by rigid thin plates 27 each disposed in a through recess 33 and situated in the radial median plane of the polygonal ring 17, that is to say, as shown by FIGS. FIGS. 2 and 4, the plane perpendicular to the longitudinal axis A of the turbomachine and containing the geometric axes B of the cylindrical receiving housings 24, the blades, equidistant from the two annular end flanks 20, 21 of the ring .
• the rigid thin plates 27 thus arranged radially prevent the deformation of the rooting zones of reduced thickness and the lateral walls 25 of the rings 23, in particular that of the rolling tracks of the bearings for rotation of the blades.
• each thin rigid plate 27 thus defines a force recovery disk formed of a plurality of stiffening ribs.
• each thin rigid plate 27 extends over the entire height of the rings 23, the lateral edges 28 of the plates being integral with the walls 25 of the rings.
• the polygonal ring 17 is obtained directly by appropriate techniques, so that the annular end flanks 20, 21, the rings 23 and the reinforcing elements 26 constitute only one and same room.
• each device corresponds to a plate 29A which carries on one side, by an articulation with axis, a tenon-mortise connection or other, the foot 15A of the blade 15, while it engages, on the other side, from outside the polygonal ring, in the housing 24 of the ring 23.
• a crown piece 29B is also mounted in the housing 24, but from inside the polygonal ring 17 to attach to the platinum and immobilize it axially, and bearings not shown, provided in the housing, between the plate and the ring, provide rotation, by appropriate means not shown, the plate relative to the housing of the polygonal ring for modify the pitch of the blades.
• the lateral walls 25 of the cylindrical rings 23 are integral with the end annular flanks 20, 21 by the rooting or connecting zones 30 provided in diametrical opposition on the lateral periphery 19 of the polygonal ring 17. The height of these zones 30 is preferably identical to that of the end annular flanks.
• the receiving housings 24 of the mounting devices 29 of the blades 15 are located, as before, at the intersection peaks of the intermediate planar zones 31 forming the polygonal lateral periphery 19 of the ring. . Obtaining the latter is done in one piece and is achieved in particular by appropriate rolling and machining techniques.
• the flat intermediate zones 31 of the lateral periphery 19 of the polygonal ring 17 comprise through recesses or openings 33, without material, between the annular flanks of end 20, 21 and the cylindrical rings 23, these intermediate flat areas 31 are solid and continuous.
• the recesses 33 are provided with reinforcing elements 26 which are, in this mode, tangential and which are each in the form of a veil or sheet of thin-walled material 35, as shown by FIGS. FIGS. 5 to 7.
• the set of these thin-walled webs 35 thus constitutes, at the lateral periphery 19 of the polygonal ring, a tangential separation partition between the inside of the polygonal ring 17, which is turned towards the turbines 5, 6 of the turbomachine 1, and the outer side which is rotated, meanwhile, to the blades 15 of the propeller 7. It is therefore clear that this partition wall can channel and thus thermally isolate the flow hot gaseous ventilation circuits of the low-pressure turbine 5 by avoiding that it passes as previously through the through recesses and disproportionately overheats the feet 15A of the blades 15 of the propeller, especially when they are made of mate Composite material, much more sensitive to heat than metallic materials. In addition to channeling the hot flow of ventilation, appropriate ventilation can be achieved at the propeller blade feet from the air of the vein.
• the webs of material 34 are obtained directly during the production of the polygonal ring 17. They could of course be reported later. Note, particularly in Figure 4, that the web of material 34 has a minimum thickness not to contribute to increase the mass of the polygonal ring.
• the thin-web reinforcing elements 26 are located substantially in the middle of the thickness of the polygonal ring 17, they could of course be at another location, between the outer and inner sides of the polygonal ring, without departing from the invention.
• the rooting zones 30 have a large thickness, covering a significant peripheral portion of the rings.
• the rooting zones 30 have a reduced thickness e (FIGS. 2 and 3), amplifying somewhat the intermediate zones.
• the thickness e may be of the order of that of the side wall of the rings.
• the reduction in the thickness of the rooting zones notably leads to reducing the influence of the traction forces exerted by the flanks on the rings and, therefore, to eliminating the risk of ovalization of those and the opposition to the pendulum movement due to the blades, which risks deforming the rooting zones then reduced, is countered by the presence of tangential sails 34 which close and stiffen the lateral periphery of the polygonal ring.
• each reinforcing member 26 could have a cross-shaped cross-section, as shown in FIG. 8, for example.
• a first thin rigid plate 27A is thus arranged in a manner identical to the previous embodiment of FIGS. 2 to 4, while a second thin plate 27B serving as a sail, perpendicular to the first and end on each side thereof, extends tangentially in the corresponding through recess 33 to come against the annular end flanks 20, 21 and the wall of the rings 23, as in the embodiment of Figures 5 to 7.
• the through-recesses 33 at the lateral periphery 19 of the polygonal ring 17 are completely closed, the set of reinforcing elements 26 in the form of a cross contributing to further stiffening the rings and the ring 17 in general, and also to isolating thermally the outer side of the hub 16, which are the blades 15, on the inner side, where are the turbines.
• the flow of hot ventilation gases circulating in the turbomachine is channeled to the inner side of the polygonal ring hub and no longer passes through the through recesses, risking to cause overheating of the blade root of the propeller, particularly critical when these are made of composite material.

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• Engineering & Computer Science (AREA)
• Aviation & Aerospace Engineering (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Structures Of Non-Positive Displacement Pumps (AREA)

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• 2010
  • 2010-12-06 CN CN201080055457.2A patent/CN102666276B/zh active Active
  • 2010-12-06 BR BR112012013757-3A patent/BR112012013757B1/pt active IP Right Grant
  • 2010-12-06 US US13/513,979 patent/US9255583B2/en active Active
  • 2010-12-06 WO PCT/EP2010/069008 patent/WO2011069981A1/fr active Application Filing
  • 2010-12-06 RU RU2012128577/06A patent/RU2559904C2/ru active
  • 2010-12-06 EP EP10787757.3A patent/EP2509860B1/fr active Active
  • 2010-12-06 JP JP2012542501A patent/JP5732067B2/ja active Active
  • 2010-12-06 CA CA2782249A patent/CA2782249C/fr active Active

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