Load reduction device and open rotor engine

Abstract

The application provides a load reduction device and an open rotor engine, and relates to the field of open rotor engines. The load reduction device comprises a peripheral frame and a roller. The peripheral frame is filled with an energy absorption structure or energy dissipation material, which is used for absorbing kinetic energy and achieving shock absorption. The roller is rotatably arranged in the peripheral frame, and the roller is in contact with the energy absorption structure or energy dissipation material in the peripheral frame, so that the swing radius of the fan rotor can be effectively reduced, and the stress concentration of the fan shaft can be weakened.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of open rotor engine, and particularly relates to a load reduction device and open rotor engine. BACKGROUND

[0002] The open rotor engine is a new type of engine between turboprop and turbofan, which can realize super large bypass ratio (30-90) and has higher propulsion efficiency than turbofan engine at high subsonic cruise conditions, and the fuel consumption is 25% lower than the current in-service engine. The application of open rotor engine is one of the important ways to realize green aviation.

[0003] In order to improve the efficiency of the open rotor engine, the fan blades are adjusted to the matching angle by the variable pitch system according to the flight condition. The fan blades of the open rotor rotate around the engine axis, so that the airflow leaving the fan blades not only has an axial velocity, but also has a circumferential rotational velocity. The fan blades are generally installed into the mounting hole of the blade wheel hub through a retaining structure (such as the cooperation of the blade handle and the bearing). The blade wheel hub is installed on the fan shaft, and is further installed on the load-bearing casing through the fan bearing. From the position of the fan bearing, the open rotor is similar to a cantilever structure. During engine operation, the fan blades rotate under the driving of the variable pitch system torque at the end of the blade handle, realizing the function of adjusting the pitch angle of the fan blades. The open rotor needs to bear the load of the blades, the aerodynamic load, and the driving load of the variable pitch system, and transmits these loads to the fan shaft through the wheel hub, and to the load-bearing casing through the fan bearing, and even to the mounting system.

[0004] The airworthiness regulation requires that the open rotor engine still maintains sufficient structural integrity after being subjected to bird strike and other accidents, and ensures the flight safety during the continuous rotation stage until the safe return. After the fan blades are subjected to bird strike and other accidents, the impact load is transmitted to the wheel hub and the fan shaft through the retaining structure, and further transmitted to the load-bearing casing. After the fan blades are damaged, not only the flow field is easy to be disturbed, but also the fan rotor may generate a huge unbalanced load, resulting in the aggravation of the fan rotor vibration and the increase of the swing amplitude. Since the open rotor part does not have an outer casing, the swing radius of the fan rotor cannot be limited, and the increase of the swing amplitude of the fan rotor will cause a series of risks such as stress concentration of the fan shaft, deformation of the variable pitch system, and the like, which may endanger the safety of the engine during the continuous rotation stage, and even cause the risk of shaft breakage. Therefore, a load reduction device is needed, which can effectively reduce the swing radius of the fan rotor and weaken the stress concentration of the fan shaft after the open rotor is damaged. SUMMARY

[0005] The present application at least aims to provide a load reduction device and open rotor engine, which can effectively reduce the swing radius of the fan rotor and weaken the stress concentration of the fan shaft.

[0006] The following presents a simplified summary of one or more aspects in order to provide a basic understanding of such aspects. This summary is not an extensive overview of all contemplated aspects, and is intended to neither identify key or critical elements of all aspects nor delineate the scope of any or all aspects. Its sole purpose is to present some concepts of one or more aspects in a simplified form as a prelude to the more detailed description that is presented later.

[0007] One of the embodiments of the present application provides a load reduction device, the load reduction device comprising a peripheral frame and a plurality of rollers. The peripheral frame is filled with an energy-absorbing structure or energy-dissipating material for absorbing kinetic energy and achieving cushioning. The plurality of rollers are rotatably arranged in series in the peripheral frame, and the plurality of rollers are in contact with the energy-absorbing structure or energy-dissipating material in the peripheral frame.

[0008] In some embodiments, the peripheral frame is a parallelogram structure.

[0009] In some embodiments, the number of rollers is a plurality.

[0010] In some embodiments, the material of the peripheral frame comprises a metal material with high strength and high toughness, so as to be able to plastically deform under the action of impact load to absorb kinetic energy.

[0011] In some embodiments, the metal material with high strength and high toughness comprises titanium alloy or nickel-based alloy.

[0012] In some embodiments, the energy-dissipating material comprises foamed aluminum, foamed nickel or elastomer material.

[0013] In some embodiments, the energy-absorbing structure comprises a net structure, a honeycomb structure, a porous structure or a spring structure.

[0014] An open rotor engine is provided in an embodiment of the present application, which comprises the load reduction device of the above-mentioned embodiments.

[0015] In some embodiments, the open rotor engine comprises a fan blade, the fan blade is mounted on a blade hub, and the blade hub is mounted on a load-bearing casing through a fan shaft, a fan bearing and a corresponding support cone wall.

[0016] The load reduction device is located between the fan blade and the fan shaft, and the peripheral frame of the load reduction device extends a fixed end, and the load reduction device is fixedly connected to the support cone wall through the fixed end.

[0017] In some embodiments, the load reduction device comprises a first side and a second side, the first side is parallel to the blade hub, and the second side is parallel to the fan shaft, and the first side and the blade hub and the second side and the fan shaft have a predetermined gap therebetween.

[0018] The plurality of rollers are arranged in series on the first side and the second side.

[0019] In some embodiments, the rollers on the first side are able to rotate about the axial rotation of the blade hub.

[0020] The rollers on the second side are able to rotate about the axial rotation of the fan shaft.

[0021] The present application relates to a load reduction device, by filling the inside of the peripheral frame with energy-absorbing structures or energy-consuming materials, and the setting of rollers on the peripheral frame, when it is subjected to external load impact, the peripheral frame deforms, the rollers rotate under impact load, and the deformation of the peripheral frame and the rotation of the rollers can absorb part of the impact load. At the same time, the deformed peripheral frame and the rotating rollers extrude and rub the internal filling energy-absorbing structures or energy-consuming materials, and the energy-absorbing structures or energy-consuming materials can also absorb part of the impact load. The load reduction device can absorb a large amount of impact load by the setting of the peripheral frame, energy-absorbing structures or energy-consuming materials and rollers, and achieve the effect of shock absorption. BRIEF DESCRIPTION OF DRAWINGS

[0022] The above features and advantages of the present application can be better understood by reading the following detailed description of embodiments of the present application in conjunction with the drawings, in which the components are not necessarily drawn to scale and components of similar or identical function or structure can have the same or similar reference numbers. In the drawings:

[0023] Figure 1 is a structural schematic diagram of a load reduction device according to some embodiments;

[0024] Figure 2 is a schematic diagram of the fan portion of an open rotor engine according to some embodiments.

[0025] BRIEF DESCRIPTION OF DRAWINGS

[0026] 1 - inlet cone;

[0027] 2 - fan blades;

[0028] 3 - blade stem;

[0029] 4 - blade hub;

[0030] 5 - fan shaft;

[0031] 6 - support cone wall;

[0032] 7 - load-bearing casing;

[0033] 8 - fan vanes;

[0034] 9 - fan bearing;

[0035] 10 - load reduction device;

[0036] 11 - peripheral frame;

[0037] 12 - roller;

[0038] 13-energy absorbing structure. DETAILED DESCRIPTION

[0039] The present application is described in detail below with reference to the attached drawing figures and specific embodiments. It is to be noted that the aspects described below with reference to the drawing figures and specific embodiments are merely exemplary and should not be understood to limit the scope of protection of the present application.

[0040] It should be understood that the terms "system", "apparatus", "unit" and / or "module" used herein are a method for distinguishing different components, elements, parts, sections or assemblies of different levels. However, if other words can achieve the same purpose, the words can be replaced by other expressions.

[0041] It can be understood that the technical terms involved in the description of the specification, such as "center", "longitudinal", "transverse", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer" and the like indicate the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the embodiments, and do not indicate or imply that the devices or elements referred to must have a particular orientation or be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the scope of protection of the application.

[0042] It should be noted that the terms "first", "second", etc. used herein to limit the features are only for the convenience of distinguishing the corresponding features, and the above terms have no special meaning unless otherwise stated. As shown in the specification and claims, the terms "one", "a", "an" and / or "the" do not refer to a single number, but also include a plurality, unless the context clearly indicates otherwise. Generally, the terms "include" and "contain" only indicate the inclusion of the steps and elements explicitly identified, and these steps and elements do not constitute an exclusive list, and the method or device can also include other steps or elements.

[0043] In the description of the specification, it should also be noted that, unless otherwise explicitly specified or limited, the terms "mount", "connect", "connect" should be understood broadly, for example, it can be a fixed connection, it can be integrally connected, or it can be detachably connected; it can be a mechanical connection, or it can be an electrical connection; it can be directly connected, or it can be indirectly connected through an intermediate medium, or the connection between two elements inside, etc. For those skilled in the art, the specific meaning of the above terms in the specification can be understood according to the specific circumstances.

[0044] Figure 1 is a structural schematic diagram of a load reduction device according to some embodiments.

[0045] The embodiment of the present specification provides a load reduction device, which can be applied to a scene requiring shock absorption and kinetic energy absorption.

[0046] As shown in Figure 1 The load reduction device 10 includes a peripheral frame 11. The peripheral frame 11 defines a cavity in its interior, which is filled with an energy absorption structure 13 or energy consumption material for absorbing kinetic energy and achieving shock absorption.

[0047] The peripheral frame 11 is a support structure of the load reduction device 10, which provides a fixed space for the energy absorption structure 13 or energy consumption material in its interior. In some embodiments, the peripheral frame 11 is a parallelogram structure, which is formed as a prism with a parallelogram cross section. The parallelogram structure has good stability and space utilization, and can effectively withstand impacts from different directions. In other embodiments, the peripheral frame 11 is other shape structure adapted to its installation space. For example, the peripheral frame 11 is formed as a cylindrical structure that can be sleeved on a shaft. For another example, the peripheral frame 11 is formed as a triangular structure. In some embodiments, the peripheral frame 11 adopts a metal material with high strength and high toughness, which can deform plastically under impact load to absorb kinetic energy. In some embodiments, the metal material with high strength and high toughness includes but is not limited to titanium alloy or nickel-based alloy. It should be noted that the load reduction device 10 can include one peripheral frame 11 or multiple peripheral frames 11.

[0048] The energy absorption structure 13 or energy consumption material is filled in the interior of the peripheral frame 11. The energy absorption structure 13 or energy consumption material can deform or convert energy when impacted, thereby effectively absorbing impact energy. When the peripheral frame 11 is subjected to external impact load, the energy absorption structure 13 or energy consumption material can effectively absorb energy after being deformed by the peripheral frame 11, thereby achieving load reduction.

[0049] In some embodiments, the energy consumption material includes aluminum foam, nickel foam or elastomer material, and also includes, for example, rubber foam, carbon fiber composite material, glass fiber composite material, etc. The energy consumption material has light weight, high energy absorption capacity and good cushioning performance. For example, the aluminum foam and the nickel foam will deform plastically when impacted, thereby absorbing a large amount of kinetic energy. The elastomer material absorbs impact force by elastic deformation.

[0050] In some embodiments, the energy absorption structure 13 includes a net-like structure, a honeycomb structure (such as an aluminum honeycomb structure), a porous structure (such as porous titanium) or a spring structure. The energy absorption structure 13 can effectively disperse and absorb energy when impacted by virtue of its unique geometry and mechanical properties. For example, the honeycomb structure has high strength and good energy absorption capacity due to its regular hexagonal arrangement. The spring structure absorbs impact energy by elastic deformation.

[0051] Rollers 12 are rotatably mounted on the outer frame 11, and contact the energy-absorbing structure 13 or energy-dissipating material within the outer frame. In some embodiments, rollers 12 are rotatably mounted on existing rods on the outer frame 11. In some embodiments, a through groove is provided on the outer frame 11, and rollers 12 are disposed within the through groove, rotatably connected to the body of the outer frame 11 via a rod or shaft. Rollers 12 protrude from the outer frame 11. The arrangement of rollers 12 allows the outer frame 11 to further absorb kinetic energy through the rotation of rollers 12 when subjected to impact, enhancing the cushioning effect, and further compressing and rubbing the energy-absorbing structure 13 or energy-dissipating material during the rotation of rollers 12, absorbing more kinetic energy. In some embodiments, there are multiple rollers 12. This helps to disperse impact force and improve the cushioning effect.

[0052] This specification provides an open rotor engine, including the load reduction device 10 described in the above embodiment. In an open rotor engine, the fan blades may be damaged during operation due to impact from external objects or fatigue, leading to increased fan rotor vibration and oscillation amplitude. This can not only cause stress concentration on the fan shaft, potentially resulting in safety accidents such as shaft breakage or severe deformation of the pitch system, but may also affect the normal operation of the engine. Therefore, the load reduction device 10 is installed in the open rotor engine to absorb the vibration and oscillation kinetic energy of the fan rotor, achieving a buffering effect on the fan rotor.

[0053] It should be noted that this specification uses the application of the load-reducing device 10 in a traction-configuration open rotary engine as an example to illustrate the application of the load-reducing device 10. However, it is not limited to the application of the load-reducing device 10 in traction-configuration open rotary engines. Those skilled in the art can make adaptive adjustments to the application of the load-reducing device 10 in other types of open rotary engines based on the content described in this specification.

[0054] Figure 2 This is a schematic diagram of the fan section of an open rotor engine according to some embodiments. Figure 1 The local area shown is Figure 2 A schematic diagram of part A in the diagram.

[0055] like Figure 2 As shown, the open rotor engine includes fan blades 2. The blade shanks 3 of the fan blades 2 are mounted on the impeller hub 4 via a retaining structure. The impeller hub 4 is connected to the fan shaft 5 and further mounted on the load-bearing casing 7 via fan bearings 9 and corresponding support cone walls 6. Figure 2The shown open-rotor engine in the traction configuration, the intake cone 1 is located at the front end of the engine, and the fan blades 2 are adjacent to the intake cone 1. A small part of the gas flowing out of the front row of fan blades 2 enters the engine through the splitter ring assembly, and most of the gas flows out after being rectified by the fan stator 8, providing thrust for the engine. In some embodiments, the fan blades 2 are generally wide-chord swept blades, and the fan blades 2 are made of composite materials.

[0056] The load reduction device 10 is located between the fan blades 2 and the fan shaft 5, and has a certain flexibility and shock absorption capacity to absorb the vibration and swing kinetic energy of the fan blades 2 and the fan shaft 5.

[0057] In some embodiments, the load reduction device 10 is located between the support cone wall 6 and the blade hub 4. The peripheral frame 11 of the load reduction device 10 extends a fixed end, and the load reduction device 10 is connected and fixed with the support cone wall 6 through the fixed end.

[0058] In some embodiments, referring to Figure 1 and Figure 2 , the load reduction device 10 is a prism with a parallelogram cross section. The load reduction device 10 includes a first side and a second side, the first side is parallel to the (axial direction of the) blade hub 4, and the second side is parallel to the (axial direction of the) fan shaft 5. There is a predetermined gap between the first side and the blade hub 4, and there is a predetermined gap between the second side and the fan shaft 5.

[0059] In some embodiments, the rollers 12 are arranged in series on the first side and the second side of the load reduction device 10. In some embodiments, the rollers 12 on the first side rotate in a direction around the axial direction of the blade hub 4. The rollers 12 on the second side rotate in a direction around the axial direction of the fan shaft 5. The rollers 12 can rotate under the action of the rotation force of the blade hub 4 or the fan shaft 5, and can rub and press the energy consumption material or energy absorption structure 13 in the peripheral frame 11, further reducing the kinetic energy of the blade hub 4 or the fan shaft 5.

[0060] When the open-rotor engine is working normally, the load reduction device 10 has a predetermined gap with the fan blade hub 4 and the fan shaft 5, and does not affect the normal operation of the open-rotor engine. When the fan blades 2 are damaged due to external impact or fatigue, the vibration of the fan rotor increases, and the swing amplitude increases, which can cause the swing amplitude of the blade hub 4 or the fan shaft 5 to increase. When the swing radius of the blade hub 4 or the fan shaft 5 exceeds the predetermined gap, it will hit the load reduction device 10 and trigger the buffer mechanism.

[0061] At this time, the blade hub 4 or the fan shaft 5 will hit the corresponding roller 12 of the load reduction device 10, driving the roller 12 to rotate. On the one hand, the rotation of the roller 12 absorbs part of the kinetic energy of the open rotor, and on the other hand, the peripheral frame 11 of the load reduction device 10 will be subjected to a large plastic deformation under the impact. At the same time, the rotating roller 12 and the deformed peripheral frame 11 will extrude the energy-absorbing material or energy-absorbing structure 13 filled in the peripheral frame 11, further absorbing the kinetic energy of the open rotor, thereby reducing the load transmitted from the fan blade 2 to the load-bearing casing 7, ensuring the safety of the load-bearing casing 7.

[0062] In addition, the shape and size of the load reduction device 10 itself can limit the maximum swing radius of the open rotor, so that the maximum stress of the fan shaft 5 is within a safe range, preventing shaft breakage events or uncoordinated events of severe deformation of the variable pitch system, ensuring the safety of the engine.

[0063] Although in some embodiments, the load reduction device 10 is installed between the fan blade 2 and the fan shaft 5, in other embodiments, the load reduction device 10 can also be installed at other positions, such as between the fan bearing 9 and the load-bearing casing, between the fan shaft 5 and the support cone wall, etc. The selection of these installation positions can be optimized according to the specific engine structure and buffering requirements to achieve the best buffering effect and structural stability.

[0064] The above has described the basic concept, and it is obvious that the above detailed disclosure is only used as an example for those skilled in the art, and does not constitute a limitation on the specification. In addition, unless the claims explicitly state, the order of processing elements and sequences in the specification, the use of numerals and letters, or the use of other names, is not intended to limit the order of the processes and methods of the specification. Although some currently considered useful embodiments of the invention are discussed in the above disclosure through various examples, it should be understood that such details are only for the purpose of illustration, and the additional claims are not limited to the disclosed embodiments, on the contrary, the claims are intended to cover all modifications and equivalent combinations that meet the spirit and scope of the embodiments.

Claims

1. An open rotor engine comprising fan blades mounted to a blade hub, the blade hub mounted to a load cell casing by a fan shaft, a fan bearing and a corresponding support cone wall, characterized by, The open rotor engine comprises a load reduction device between the fan blades and the fan shaft, The load reduction device comprises: a peripheral frame filled with energy-absorbing structures or energy-dissipating materials for absorbing kinetic energy and achieving shock absorption, the peripheral frame extending out of a fixed end, the load reduction device being fixed with the supporting cone wall through the fixed end; rollers rotatably arranged in series on the peripheral frame, the rollers being in contact with the energy-absorbing structures or the energy-dissipating materials in the peripheral frame, the rollers rubbing against the energy-absorbing structures or the energy-dissipating materials during rotation; The load reduction device comprises a first side and a second side, the first side having a predetermined gap with the blade hub, and the second side having a predetermined gap with the fan shaft; The rollers are arranged in series on the first side and the second side, the rollers on the first side having a gap with the blade hub, and the rollers on the second side having a gap with the fan shaft.

2. The open-rotor engine of claim 1, wherein The peripheral frame is a parallelogram structure, and the number of the rollers is multiple.

3. The open-rotor engine of claim 1, wherein The material of the peripheral frame comprises titanium alloy or nickel-based alloy, so as to be plastically deformed to absorb kinetic energy under impact load.

4. The open-rotor engine of claim 1, wherein The energy-dissipating materials comprise foamed aluminum, foamed nickel or elastomer materials.

5. The open-rotor engine of claim 1, wherein The energy-absorbing structures comprise net-like structures, porous structures or spring structures.

6. The open-rotor engine of claim 1, wherein The first side is parallel to the blade hub, and the second side is parallel to the fan shaft.

7. The open-rotor engine of claim 6, wherein The rollers on the first side can produce rotation around the axial direction of the blade hub; The rollers on the second side can produce rotation around the axial direction of the fan shaft.

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