Three-spool turbofan engine

Abstract

The present disclosure relates to a three-spool turbofan engine, which includes a fan component, a booster stage component, a core engine component, a contra-rotating low-pressure turbine component, an intermediate bearing frame, and an inter-stage bearing frame; the fan rotor is connected to the outer rotor of the low-pressure turbine through a first rotating shaft, the booster stage rotor is connected to the inner rotor of the low-pressure turbine through a second rotating shaft, the fan rotor is supported at the front end of the axial direction of the booster stage rotor through a first intermediate bearing, and the outer rotor of the low-pressure turbine is supported at the rear end of the axial direction of the inner rotor of the low-pressure turbine through a second intermediate bearing. The three-spool turbofan engine of the present disclosure reduces the length of the engine and decreases the weight of the engine; the stator of the low-pressure turbine is fixed on the inter-stage bearing frame, solving the problem of speed matching among the fan, the booster stage, and the low-pressure turbine, reducing the structural complexity of the engine, improving the reliability and safety of the engine, and enhancing the propulsion efficiency of the engine.

Description

Technical Field

[0001] The present disclosure relates to a three-spool turbofan engine. Background Art

[0002] The statements herein only provide background information related to the present disclosure and do not necessarily constitute related art.

[0003] Performance requirements of commercial aero-engines such as high thrust, low fuel consumption, high reliability, long life, low noise and low emissions pose great challenges to the design of aero-engines. Current two-spool and three-spool turbofan engines have improved the propulsion efficiency of commercial aero-engines to varying degrees, but also face some problems and challenges.

[0004] Traditional two-spool turbofan engines can improve the propulsion efficiency by increasing the fan diameter and the bypass ratio. According to the relationship between the linear velocity and the angular velocity, the tip tangential velocity of the fan blade is determined by the product of the fan speed and the diameter. The tip tangential velocity of the fan blade is limited by the shock noise, and the fan speed is determined by the speed of the turbine rotor coaxial with it. When the speed of the turbine rotor is determined, the maximum value that the fan diameter can reach is basically determined, and it is impossible to further increase the bypass ratio by increasing the fan diameter. The three-spool engine invented by Rolls-Royce adds an intermediate-pressure turbine rotor between the high-pressure and low-pressure turbines. This intermediate-pressure turbine rotor is connected to the booster stage, while the low-pressure turbine rotor is connected to the fan rotor, solving the speed matching problem of the fan, booster stage and turbine. Compared with the two-spool turbofan engine, the three-spool turbofan engine can further reduce the speed of the low-pressure turbine and design a larger-diameter fan to obtain greater thrust and propulsion efficiency. However, the three-spool turbofan engine adds an intermediate-pressure turbine, which undoubtedly increases the length of the engine, increases the weight of the engine, and the complexity of its support and lubrication system structures is much higher than that of the two-spool turbofan engine, posing challenges to the reliability and safety of the engine. Summary of the Invention

[0005] One technical problem to be solved by the present disclosure is to provide a three-spool turbofan engine that can improve the propulsion efficiency of the engine.

[0006] Some embodiments of the present disclosure provide a three-spool turbofan engine, including: a fan component including a fan rotor; a booster stage component including a booster stage rotor; a core engine component including a high-pressure compressor rotor and a high-pressure turbine rotor; a contra-rotating low-pressure turbine component including a contra-rotating low-pressure turbine rotor, the contra-rotating low-pressure turbine rotor including a low-pressure turbine stator and a low-pressure turbine outer rotor and a low-pressure turbine inner rotor with opposite rotation directions; an intermediate bearing frame located between the booster stage rotor and the high-pressure compressor rotor, configured to support the booster stage rotor and the high-pressure compressor rotor; and an inter-stage bearing frame located between the high-pressure turbine rotor and the contra-rotating low-pressure turbine rotor, configured to fix the low-pressure turbine stator and support the low-pressure turbine inner rotor; wherein, the fan rotor is connected to the low-pressure turbine outer rotor through a first rotating shaft, the booster stage rotor is connected to the low-pressure turbine inner rotor through a second rotating shaft, the fan rotor is supported on the front axial end of the booster stage rotor through a first intermediate bearing, and the low-pressure turbine outer rotor is supported on the rear axial end of the low-pressure turbine inner rotor through a second intermediate bearing.

[0007] In some embodiments, the low-pressure turbine outer rotor is configured as a drum-type rotor with low-pressure turbine outer rotor blades, the low-pressure turbine inner rotor is configured as a disk-type rotor with low-pressure turbine inner rotor blades, the low-pressure turbine stator includes low-pressure turbine stator blades, and in the direction of the gas flow, the low-pressure turbine stator blades and the low-pressure turbine outer rotor blades are arranged alternately, the low-pressure turbine outer rotor blades and the low-pressure turbine inner rotor blades are arranged alternately, and the sum of the number of stages of the low-pressure turbine stator and the number of stages of the low-pressure turbine inner rotor is equal to the number of stages of the low-pressure turbine outer rotor.

[0008] In some embodiments, the number of stages of the low-pressure turbine stator is 2, the number of stages of the low-pressure turbine outer rotor is 4, and the number of stages of the low-pressure turbine inner rotor is 2.

[0009] In some embodiments, the number of stages of the low-pressure turbine stator is equal to the number of stages of the low-pressure turbine inner rotor.

[0010] In some embodiments, the number of stages of the low-pressure turbine inner rotor is equal to the number of stages of the booster stage rotor.

[0011] In some embodiments, the booster stage rotor is supported on the intermediate bearing frame through a first bearing, the second rotating shaft is supported on the intermediate bearing frame through a second bearing, the first bearing is a ball bearing, and the second bearing is a roller bearing.

[0012] In some embodiments, the outer ring of the first intermediate bearing is connected to the booster stage rotor through a first bearing support, the inner ring of the first intermediate bearing is connected to the fan rotor, and the first intermediate bearing is a ball bearing.

[0013] In some embodiments, the low-pressure turbine inner rotor is supported on the inter-stage load-bearing frame by a fifth bearing. The inner ring of the second intermediate bearing is connected to the low-pressure turbine inner rotor, and the outer ring of the second intermediate bearing is connected to the low-pressure turbine outer rotor.

[0014] In some embodiments, both the fifth bearing and the second intermediate bearing are roller bearings.

[0015] In the technical solution of the present disclosure, the fan rotor is supported on the front end of the booster rotor shaft by a first intermediate bearing, and the low-pressure turbine outer rotor is supported on the rear end of the low-pressure turbine inner rotor shaft by a second intermediate bearing, reducing the length of the engine and the weight of the engine; the low-pressure turbine stator is fixed on the inter-stage load-bearing frame, solving the speed matching problem of the fan, booster stage and low-pressure turbine, reducing the structural complexity of the engine, improving the reliability and safety of the engine, and improving the propulsion efficiency of the engine. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions in the embodiments of the present disclosure or related technologies, the following will briefly introduce the drawings required for the description of the embodiments or related technologies. Obviously, the drawings in the following description are only some embodiments of the present disclosure. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0017] Figure 1 FIG. is a schematic diagram of the overall structure of some embodiments of a three-rotor turbofan engine according to the present disclosure;

[0018] Figure 2 FIG. is a schematic diagram of the front part of the shaft of some embodiments of a three-rotor turbofan engine according to the present disclosure;

[0019] Figure 3 FIG. is a schematic diagram of the rear part of the shaft of some embodiments of a three-rotor turbofan engine according to the present disclosure.

[0020] DESCRIPTION OF THE REFERENCE NUMERALS

[0021] 1. Casing; 2. Fan rotor; 3. Booster stage rotor; 4. Intermediate bearing frame; 5. High-pressure compressor rotor; 6. High-pressure turbine rotor; 7. Inter-stage bearing frame; 8. Contra-rotating low-pressure turbine rotor; 9. Fan rotor blades; 10. Booster stage rotor blades; 11. High-pressure compressor rotor blades; 12. High-pressure turbine rotor blades; 13. First intermediate bearing; 14. First bearing; 15. Second bearing; 16. Third bearing; 17. Fourth bearing; 18. Fifth bearing; 19. Second intermediate bearing; 20. First rotating shaft; 21. Second rotating shaft; 22. First bearing support; 23. Front connecting section of the second rotating shaft; 24. Second bearing support; 25. Third bearing support; 26. Fourth bearing support; 27. Fifth bearing support; 28. Sixth bearing support; 29. Rear connecting section of the second rotating shaft; 30. Rear connecting section of the first rotating shaft; 31. Low-pressure turbine stator support section; 32. Low-pressure turbine outer rotor; 33. Low-pressure turbine inner rotor; 34. Low-pressure turbine stator; 35. Low-pressure turbine outer rotor blades; 36. Low-pressure turbine inner rotor blades; 37. Low-pressure turbine stator blades; 38. Inner ring support section of the second intermediate bearing; 39. Outer ring support section of the second intermediate bearing; 40. Inner ring support section of the fifth bearing. Detailed implementation manners

[0022] Various exemplary embodiments of the present disclosure will now be described in detail with reference to the accompanying drawings. The description of the exemplary embodiments is merely illustrative and in no way limits the present disclosure and its application or use. The present disclosure can be implemented in many different forms and is not limited to the embodiments herein. These embodiments are provided to make the present disclosure thorough and complete, and to fully convey the scope of the present disclosure to those skilled in the art. It should be noted that: Unless otherwise specifically stated, the relative arrangements of components and steps, the components of materials, numerical expressions and values set forth in these embodiments should be construed as merely exemplary and not as limitations.

[0023] The terms "first", "second" and similar terms used in the present disclosure do not denote any order, quantity or importance, but are only used to distinguish different parts. The terms such as "comprising" or "including" mean that the elements before this term cover the elements listed after this term, and do not exclude the possibility of also covering other elements. The terms such as "upper", "lower", "left" and "right" are only used to represent relative positional relationships, and when the absolute position of the object being described changes, the relative positional relationship may also change accordingly.

[0024] In the present disclosure, when it is described that a specific device is located between a first device and a second device, there may or may not be an intermediate device between the specific device and the first device or the second device. When it is described that a specific device is connected to other devices, the specific device may be directly connected to other devices without an intermediate device, or may not be directly connected to other devices but have an intermediate device.

[0025] All terms used in the present disclosure have the same meanings as those understood by those of ordinary skill in the art to which the present disclosure pertains, unless otherwise specifically defined. It should also be understood that terms defined in a general dictionary, such as those, should be interpreted as having meanings consistent with their meanings in the context of the relevant art, and should not be interpreted in an idealized or overly formal sense, unless specifically defined as such herein.

[0026] Technologies, methods, and devices known to those of ordinary skill in the relevant art may not be discussed in detail, but where appropriate, the technologies, methods, and devices should be regarded as part of the specification.

[0027] Combined Figures 1 to 3 As shown, some embodiments of the present disclosure provide a three-spool turbofan engine, which includes a casing 1, a fan component, a booster stage component, a fan component, a core engine component, a contra-rotating low-pressure turbine component, an intermediate bearing frame 4, and an inter-stage bearing frame 7. Among them, the fan component includes a fan rotor 2 and fan rotor blades 9; the booster stage component includes a booster stage rotor 3 and booster stage rotor blades 10; the core engine component includes a high-pressure compressor rotor 5 and a high-pressure turbine rotor 6. High-pressure compressor rotor blades 11 are installed on the high-pressure compressor rotor 5, and high-pressure turbine rotor blades 12 are installed on the high-pressure turbine rotor 6. The high-pressure compressor rotor 5 and the high-pressure turbine rotor 6 are connected by a rigid rotor coupling and form a third rotating shaft, and are supported on the intermediate bearing frame 4 and the inter-stage bearing frame 7 through a third bearing 16 and a fourth bearing 17 respectively; the contra-rotating low-pressure turbine component includes a contra-rotating low-pressure turbine rotor 8. The contra-rotating low-pressure turbine rotor 8 includes a low-pressure turbine stator 34 and a low-pressure turbine outer rotor 32 and a low-pressure turbine inner rotor 33 with opposite rotation directions. The low-pressure turbine stator 34 includes low-pressure turbine stator blades 37. Low-pressure turbine outer rotor blades 35 are installed on the low-pressure turbine outer rotor 32, and low-pressure turbine inner rotor blades 36 are installed on the low-pressure turbine inner rotor 33. The contra-rotating low-pressure turbine structure is adopted, which can obtain a greater work effect under the condition of a lower low-pressure turbine rotor speed, and the lower low-pressure turbine rotor speed enables the low-pressure turbine efficiency to be maintained at a large fan diameter.

[0028] As Figure 1 and Figure 2 As shown, the intermediate bearing frame 4 is located between the booster stage rotor 3 and the high-pressure compressor rotor 5, and is configured to support the booster stage rotor 3 and the high-pressure compressor rotor 5; AsFigure 1 and Figure 3 As shown, the intermediate load-bearing frame 7 is located between the high-pressure turbine rotor 6 and the contra-rotating low-pressure turbine rotor 8, and is configured to fix the low-pressure turbine stator 34 and support the low-pressure turbine inner rotor 33; as Figure 1 shown, the fan rotor 2 is connected to the low-pressure turbine outer rotor 32 through the first rotating shaft 20, the booster stage rotor 3 is connected to the low-pressure turbine inner rotor 33 through the second rotating shaft 21, the fan rotor 2 is supported at the front end of the axial direction of the booster stage rotor 3 through the first intermediate bearing 13, and the low-pressure turbine outer rotor 32 is supported at the rear end of the axial direction of the low-pressure turbine inner rotor 33 through the second intermediate bearing 19.

[0029] In this schematic embodiment, the fan rotor 2 is supported at the front end of the axial direction of the booster stage rotor 3 through the first intermediate bearing 13, and the low-pressure turbine outer rotor 32 is supported at the rear end of the axial direction of the low-pressure turbine inner rotor 33 through the second intermediate bearing 19, so that there is no need to separately provide a support structure, reducing the length of the engine and the weight of the engine; the low-pressure turbine stator 34 is fixed on the intermediate load-bearing frame 7 through the low-pressure turbine stator support section 31, solving the problem of rotational speed matching of the fan, booster stage and low-pressure turbine, reducing the structural complexity of the engine, and improving the reliability, safety and propulsion efficiency of the engine.

[0030] As Figures 1 to 3 shown, in some embodiments, the low-pressure turbine outer rotor 32 is configured as a drum-type rotor, the low-pressure turbine inner rotor 33 is configured as a disk-type rotor, and in the direction of the gas flow, the low-pressure turbine stator blades 37 and the low-pressure turbine outer rotor blades 35 are arranged in an interlaced manner, the low-pressure turbine outer rotor blades 35 and the low-pressure turbine inner rotor blades 36 are arranged in an interlaced manner, and the sum of the number of stages of the low-pressure turbine stator 34 and the number of stages of the low-pressure turbine inner rotor 33 is equal to the number of stages of the low-pressure turbine outer rotor 32, which is beneficial to meeting the rotational speed matching of the fan, booster stage and low-pressure turbine and improving the propulsion efficiency.

[0031] As Figure 3 shown, in some embodiments, the number of stages of the low-pressure turbine stator 34 is 2, and its number of stages can be adjusted according to the number of stages of the low-pressure turbine inner rotor 33. The number of stages of the low-pressure turbine outer rotor 32 is 4, and the number of stages of the low-pressure turbine inner rotor 33 is 2. The purpose is to match the torque required by the booster stage rotor 3, and its number of stages can be increased or decreased according to the actual required torque.

[0032] Similarly, in order to effectively improve the propulsion efficiency, in some embodiments, the number of stages of the low-pressure turbine inner rotor 33 is equal to the number of stages of the booster stage rotor 3.

[0033] In some embodiments, the number of stages of the low-pressure turbine stator 34 is equal to the number of stages of the low-pressure turbine inner rotor 33, ensuring that the driving torque of the low-pressure turbine inner rotor 33 matches the torque required by the booster stage rotor 3.

[0034] As Figure 1 and Figure 2 shown, in some embodiments, the booster stage rotor 3 is supported on the second bearing support 24 of the intermediate bearing frame 4 through the front end connection section 23 of the second rotating shaft and the first bearing 14. The second rotating shaft 21 is supported on the third bearing support 25 of the intermediate bearing frame 4 through the second bearing 15. The high-pressure compressor rotor 5 is supported on the fourth bearing support 26 of the intermediate bearing frame 4 through the third bearing 16. The first bearing 14 is a ball bearing, and the second bearing 15 is a roller bearing to ensure the support stability and reliability.

[0035] As Figure 1 and Figure 2 shown, in some embodiments, the outer ring of the first intermediate bearing 13 is connected to the first bearing support 22 on the booster stage rotor 3 through the first bearing support 22. The inner ring of the first intermediate bearing 13 is connected to the fan rotor 2. The first intermediate bearing 13 is a ball bearing to ensure the support stability and reliability.

[0036] As Figure 1 and Figure 3 shown, in some embodiments, the high-pressure turbine rotor 6 is supported on the fifth bearing support 27 of the inter-stage bearing frame 7 through the fourth bearing 17. The low-pressure turbine inner rotor 33 is supported on the sixth bearing support 28 of the inter-stage bearing frame 7 through the fifth bearing 18. The outer ring of the fifth bearing 18 is connected to the sixth bearing support 28. The inner ring of the fifth bearing 18 is connected to the rear end connection section 29 of the second rotating shaft of the low-pressure turbine inner rotor 33 through the fifth bearing inner ring support section 40. The inner ring of the second intermediate bearing 19 is connected to the rear end connection section 29 of the second rotating shaft through the second intermediate bearing inner ring support section 38. The outer ring of the second intermediate bearing 19 is connected to the low-pressure turbine outer rotor 32 through the second intermediate bearing outer ring support section 39 and the rear connection section 30 of the first rotating shaft. The structure is reasonably arranged and has high feasibility.

[0037] In some embodiments, as Figure 1 shown, both the fifth bearing 18 and the second intermediate bearing 19 are roller bearings to ensure the support stability and reliability.

[0038] So far, the embodiments of the present disclosure have been described in detail. To avoid obscuring the concept of the present disclosure, some details well known in the art have not been described. Those skilled in the art can clearly understand how to implement the technical solutions disclosed here based on the above description.

[0039] Although some specific embodiments of the present disclosure have been described in detail by way of examples, those skilled in the art should understand that the above examples are for illustrative purposes only and are not intended to limit the scope of the present disclosure. Those skilled in the art should understand that the above embodiments can be modified or equivalent substitutions can be made to some technical features without departing from the scope and spirit of the present disclosure. The scope of the present disclosure is defined by the appended claims.

Claims

1. A three-spool turbofan engine, characterized in that, Comprising: A fan component, which includes a fan rotor (2); A booster stage component, which includes a booster stage rotor (3); A core engine component, which includes a high-pressure compressor rotor (5) and a high-pressure turbine rotor (6); A contra-rotating low-pressure turbine component, which includes a contra-rotating low-pressure turbine rotor (8), and the contra-rotating low-pressure turbine rotor (8) includes a low-pressure turbine stator (34) and a low-pressure turbine outer rotor (32) and a low-pressure turbine inner rotor (33) with opposite rotation directions; An intermediate bearing frame (4), located between the booster stage rotor (3) and the high-pressure compressor rotor (5), and is configured to support the booster stage rotor (3) and the high-pressure compressor rotor (5); and An inter-stage bearing frame (7), located between the high-pressure turbine rotor (6) and the contra-rotating low-pressure turbine rotor (8), and is configured to fix the low-pressure turbine stator (34) and support the low-pressure turbine inner rotor (33); Wherein, the fan rotor (2) is connected to the low-pressure turbine outer rotor (32) through a first rotating shaft (20), the booster stage rotor (3) is connected to the low-pressure turbine inner rotor (33) through a second rotating shaft (21), the fan rotor (2) is supported at the front end of the axial direction of the booster stage rotor (3) through a first intermediate bearing (13), and the low-pressure turbine outer rotor (32) is supported at the rear end of the axial direction of the low-pressure turbine inner rotor (33) through a second intermediate bearing (19); the low-pressure turbine outer rotor (32) is configured as a drum-type rotor with low-pressure turbine outer rotor blades (35), the low-pressure turbine inner rotor (33) is configured as a disk-type rotor with low-pressure turbine inner rotor blades (36), the low-pressure turbine stator (34) includes low-pressure turbine stator blades (37), and in the direction of the airflow, the low-pressure turbine stator blades (37) are arranged alternately with the low-pressure turbine outer rotor blades (35), the low-pressure turbine outer rotor blades (35) and the low-pressure turbine inner rotor blades (36) are arranged alternately, and the sum of the number of stages of the low-pressure turbine stator (34) and the number of stages of the low-pressure turbine inner rotor (33) is equal to the number of stages of the low-pressure turbine outer rotor (32).

2. The three-spool turbofan engine according to claim 1, wherein, The number of stages of the low-pressure turbine stator (34) is 2, the number of stages of the low-pressure turbine outer rotor (32) is 4, and the number of stages of the low-pressure turbine inner rotor (33) is 2.

3. The three-spool turbofan engine according to claim 1, wherein The number of stages of the low-pressure turbine stator (34) is equal to the number of stages of the low-pressure turbine inner rotor (33).

4. The three-spool turbofan engine according to claim 1, characterized in that The number of stages of the low-pressure turbine inner rotor (33) is equal to the number of stages of the booster stage rotor (3).

5. The three-spool turbofan engine according to claim 1, characterized in that, The booster stage rotor (3) is supported on the intermediate bearing frame (4) through a first bearing (14), the second rotating shaft (21) is supported on the intermediate bearing frame (4) through a second bearing (15), the first bearing (14) is a ball bearing, and the second bearing (15) is a roller bearing.

6. The three-spool turbofan engine according to claim 5, characterized in that, The outer ring of the first intermediate bearing (13) is connected to the booster stage rotor (3) through a first bearing support (22), the inner ring of the first intermediate bearing (13) is connected to the fan rotor (2), and the first intermediate bearing (13) is a ball bearing.

7. The three-spool turbofan engine according to claim 1, characterized in that, The low-pressure turbine inner rotor (33) is supported on the inter-stage load-bearing frame (7) through a fifth bearing (18). The inner ring of the second intermediate bearing (19) is connected to the low-pressure turbine inner rotor (33), and the outer ring of the second intermediate bearing (19) is connected to the low-pressure turbine outer rotor (32).

8. The three-spool turbofan engine according to claim 7, characterized in that, Both the fifth bearing (18) and the second intermediate bearing (19) are roller bearings.

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