A high-bypass-ratio turbofan engine power system based on a rotating casing and a design method thereof

Abstract

A kind of high-bypass-ratio turbofan engine power system and design method based on rotating casing, the present application relates to the field of aero-engine, solve the size of existing fan increases so that the tip tangential velocity of turbofan engine will increase accordingly, leading to noise increase, efficiency reduction, exceed the strength limit of material and increase rotor dynamics etc.Problems.The system includes fan, first stage compressor, rotating casing etc., the fan is arranged in the inside of the outer end surface of stationary casing, one outlet end of fan is communicated with outer channel, another outlet end is communicated with low pressure compressor inlet end;Rotating casing is connected with first stage compressor and first stage low pressure turbine respectively.Fan and low pressure compressor and low pressure turbine are connected by transmission shaft;High pressure compressor and high pressure turbine are connected by transmission shaft;Combustion chamber is fixed in the inside of inner end surface of stationary casing;Tail nozzle inlet is connected with first stage low pressure turbine outlet.It is also applicable to the field of using rotating casing design fan size of turbofan engine.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of aero-engines, in particular to a high-bypass-ratio turbofan engine power system based on a rotating casing and a design method. BACKGROUND

[0002] A high-bypass-ratio turbofan engine has the advantages of high efficiency, low fuel consumption, large thrust, low noise, long range, high reliability, etc., and is a research and application hotspot in the field of aero-engines. The fan outer diameter and tip speed are important parameters affecting aerodynamic performance. With the increase of the bypass ratio, the fan outer diameter usually increases to provide greater airflow flow.

[0003] However, modern high-bypass-ratio turbofan engines have to reduce the number of fan blades in order to reduce weight and improve aerodynamic efficiency. At the same time, the increase in fan radius also increases the tip tangential speed of the turbofan engine, resulting in increased noise, reduced efficiency, and possibly exceeding the strength limit of the material.

[0004] In addition, the fan and the low-pressure turbine are usually mechanically connected and have the same speed. If the fan size is too large, the low-pressure turbine also needs to be increased, which will cause the flow passage between the high and low pressure turbines to become steep, increasing the rotor dynamics problem. Based on the above reasons, a high-bypass-ratio turbofan engine power system based on a rotating casing is proposed to reduce the size of the fan. SUMMARY

[0005] The present application solves the problem of the increase in fan size, which increases the tip tangential speed of the turbofan engine, resulting in increased noise, reduced efficiency, and possibly exceeding the strength limit of the material, and increases the rotor dynamics.

[0006] To solve the above technical problems, the present application is realized by the following technical scheme:

[0007] Scheme one, the present application proposes a high-bypass-ratio turbofan engine power system based on a rotating casing, which comprises a fan, a primary compressor, a rotating casing, a low-pressure compressor, a high-pressure compressor, a combustion chamber, a high-pressure turbine, a low-pressure turbine, a primary low-pressure turbine, an exhaust nozzle, a stationary casing inner end face, and a stationary casing outer end face.

[0008] The fan is arranged inside the stationary casing outer end face, one outlet end of the fan is in communication with the outer bypass duct, and the other outlet end is in communication with the low-pressure compressor inlet end.

[0009] The low-pressure compressor, high-pressure compressor, combustion chamber, high-pressure turbine, low-pressure turbine, primary low-pressure turbine, and exhaust nozzle are arranged in sequence in the axial direction.

[0010] The first stage compressor and the first stage low pressure turbine are provided with a blade tip casing, which is fixedly connected with the rotating casing;

[0011] The fan, the low pressure compressor and the low pressure turbine are connected through a transmission shaft;

[0012] The high pressure compressor and the high pressure turbine are connected through a transmission shaft;

[0013] The combustion chamber is fixedly connected with the inner side of the inner end surface of the stationary casing; and the tail nozzle inlet is connected with the outlet of the first stage low pressure turbine.

[0014] Further, a preferred embodiment is provided, wherein a third channel is arranged between the outer end surface of the stationary casing and the rotating casing; the first stage compressor is arranged in the third channel; and the first stage low pressure turbine is arranged inside the inner end surface of the stationary casing.

[0015] Further, a preferred embodiment is provided, wherein the rotating casing is driven to rotate by the first stage low pressure turbine.

[0016] Further, a preferred embodiment is provided, wherein the fan is arranged in an axial direction and in front of the inner end surface of the stationary casing; and the low pressure compressor, the high pressure compressor, the combustion chamber, the high pressure turbine, the low pressure turbine, the first stage low pressure turbine and the tail nozzle are arranged inside the inner end surface of the stationary casing.

[0017] Further, a preferred embodiment is provided, wherein the fan, the first stage compressor, the low pressure compressor, the high pressure compressor, the combustion chamber, the high pressure turbine, the low pressure turbine, the first stage low pressure turbine and the tail nozzle are arranged inside the rotating casing respectively.

[0018] Further, a preferred embodiment is provided, wherein the system further comprises a step of optimizing the ratio of the diameter of the rotating casing to the diameter of the fan.

[0019] Further, a preferred embodiment is provided, wherein the first stage compressor further comprises a step of adjusting power for different flight conditions.

[0020] Scheme II: A design method of the rotating casing based high bypass ratio turbofan engine power system according to any one of the schemes I, the design method comprising the following steps:

[0021] designing working condition parameters, calculating the specific fuel consumption and unit thrust of the rotating casing based high bypass ratio turbofan engine power system, and obtaining the optimal specific fuel consumption and unit thrust by comparing the calculated specific fuel consumption and unit thrust of the rotating casing based high bypass ratio turbofan engine power system and other engine power systems.

[0022] Further, a preferred embodiment is provided, wherein the working condition parameters include flight altitude, fan pressure ratio and third bypass ratio.

[0023] The present application has the advantages of:

[0024] The large-bypass-ratio turbofan engine power system based on a rotating casing of the present application applies the rotating casing to the turbofan engine power system scheme, uses the rotating casing to reduce the fan size of the existing turbofan engine, effectively reduces the tip tangential velocity, reduces the aerodynamic noise, and reduces the stress on the blades and the casing, reduces the structural strength requirement of the fan material and the manufacturing cost, and reduces the centrifugal force and vibration amplitude of the internal rotor, thereby reducing the rotor dynamics problem.

[0025] The rotating casing design of the present application maintains the existing turbofan engine fan design level, further improves the bypass ratio of the turbofan engine by adding a third bypass, and is beneficial to improve the output power and thermal efficiency of the engine system, thereby reducing the fuel consumption rate of the turbofan engine and reducing the flight cost of the aircraft.

[0026] The present application is also suitable for the field of fan size of the turbofan engine using the rotating casing design. BRIEF DESCRIPTION OF DRAWINGS

[0027] Figure 1 The schematic diagram of the overall structure of the large-bypass-ratio turbofan engine power system based on a rotating casing according to the first embodiment is shown. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme of the embodiments of the present application will be described clearly and completely below in combination with the drawings of the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, but not all the embodiments of the present application.

[0029] Embodiment one, the present embodiment proposes a large-bypass-ratio turbofan engine power system based on a rotating casing, which comprises a fan 1, a first-stage compressor 2, a rotating casing 3, a low-pressure compressor 5, a high-pressure compressor 6, a combustion chamber 7, a high-pressure turbine 8, a low-pressure turbine 9, a first-stage low-pressure turbine 4, an exhaust nozzle 10, a stationary casing inner end face 11 and a stationary casing outer end face 12.

[0030] The fan 1 is arranged inside the stationary casing outer end face 12, one outlet end of the fan 1 is communicated with the outer bypass, and the other outlet end is communicated with the inlet end of the low-pressure compressor 5;

[0031] The low pressure compressor 5, the high pressure compressor 6, the combustion chamber 7, the high pressure turbine 8, the low pressure turbine 9, the first stage low pressure turbine 4 and the tail nozzle 10 are arranged in sequence in the axial direction.

[0032] The first stage compressor 2 and the first stage low pressure turbine 4 are provided with a blade tip casing which is fixedly connected with the rotating casing 3.

[0033] The fan 1 is connected with the low pressure compressor 5 and the low pressure turbine 9 through a transmission shaft.

[0034] The high pressure compressor 6 is connected with the high pressure turbine 8 through a transmission shaft.

[0035] The combustion chamber 7 is fixed to the inner side of the inner end face 11 of the stationary casing; the inlet of the tail nozzle 10 is connected with the outlet of the first stage low pressure turbine 4.

[0036] Embodiment two, the embodiment is further limited to the large bypass ratio turbofan engine power system based on the rotating casing of the first embodiment, the third channel is arranged between the outer end face 12 of the stationary casing and the rotating casing 3; the first stage compressor 2 is located on the third channel; the first stage low pressure turbine 4 is located on the inner side of the inner end face 11 of the stationary casing.

[0037] Embodiment three, the embodiment is further limited to the large bypass ratio turbofan engine power system based on the rotating casing of the first embodiment, the rotating casing 3 is driven to rotate by the first stage low pressure turbine 4.

[0038] Embodiment four, the embodiment is further limited to the large bypass ratio turbofan engine power system based on the rotating casing of the first embodiment, the fan 1 is arranged in the axial direction and located in front of the inner end face 11 of the stationary casing; the low pressure compressor 5, the high pressure compressor 6, the combustion chamber 7, the high pressure turbine 8, the low pressure turbine 9, the first stage low pressure turbine 4 and the tail nozzle 10 are located on the inner side of the inner end face 11 of the stationary casing.

[0039] Embodiment five, the embodiment is further limited to the large bypass ratio turbofan engine power system based on the rotating casing of the first embodiment, the fan 1, the first stage compressor 2, the low pressure compressor 5, the high pressure compressor 6, the combustion chamber 7, the high pressure turbine 8, the low pressure turbine 9, the first stage low pressure turbine 4, the tail nozzle 10, the inner end face 11 of the stationary casing and the outer end face 12 of the stationary casing are respectively arranged on the inner side of the rotating casing 3.

[0040] Embodiment six, the embodiment is further limited to the large bypass ratio turbofan engine power system based on the rotating casing of the first embodiment, the system further comprises the step of optimizing the design of the diameter ratio of the rotating casing 3 to the diameter of the fan 1.

[0041] Embodiment seven, the embodiment is a further limitation of the high-bypass-ratio turbofan engine power system based on rotating cowl described in Embodiment six, the ratio of the diameter of rotating cowl 3 to the diameter of fan 1 is in the range of 0.1 to 0.4.

[0042] Embodiment eight, the embodiment is a further limitation of the high-bypass-ratio turbofan engine power system based on rotating cowl described in Embodiment six, the first-stage compressor 2 further comprises the step of power adjustment for different flight conditions.

[0043] Embodiment nine, the embodiment proposes a design method for the high-bypass-ratio turbofan engine power system based on rotating cowl described in any one of Embodiments one to eight, the design method comprises the following steps:

[0044] Designing working condition parameters, calculating the specific fuel consumption and unit thrust of the high-bypass-ratio turbofan engine power system based on rotating cowl, and obtaining the optimal specific fuel consumption and unit thrust by comparing the calculated specific fuel consumption and unit thrust of the high-bypass-ratio turbofan engine power system and other engine power systems.

[0045] Embodiment ten, the embodiment is a further limitation of the design method of the high-bypass-ratio turbofan engine power system based on rotating cowl described in Embodiment nine, the working condition parameters include flight altitude, fan pressure ratio and third bypass ratio.

[0046] Embodiment eleven, the embodiment proposes an example for explaining Embodiments one to ten, the example is specifically:

[0047] Reference Figure 1The application discloses a high-bypass-ratio turbofan engine power system based on a rotating casing, which comprises a fan, a primary compressor, a rotating casing, a low-pressure compressor, a high-pressure compressor, a combustion chamber, a high-pressure turbine, a low-pressure turbine, a primary low-pressure turbine, a tail nozzle, an inner end surface of a stationary casing and an outer end surface of the stationary casing. The fan is located inside the outer end surface of the stationary casing, and has one outlet end communicated with an outer channel and another outlet end communicated with an inlet end of the low-pressure compressor. The low-pressure compressor, the high-pressure compressor, the combustion chamber, the high-pressure turbine, the low-pressure turbine, the primary low-pressure turbine and the tail nozzle are sequentially arranged in an axial direction. The blade tip casing of the primary compressor and the primary low-pressure turbine is fixedly connected with the rotating casing. The fan is connected with the low-pressure compressor and the low-pressure turbine through a transmission shaft. The high-pressure compressor is connected with the high-pressure turbine through a transmission shaft. The combustion chamber is fixedly arranged inside an inner end surface of the stationary casing. The tail nozzle inlet is connected with the outlet of the primary low-pressure turbine. The channel between the outer end surface of the stationary casing and the rotating casing is a third channel. The primary compressor is located in the third channel. The primary low-pressure turbine is located inside the inner end surface of the stationary casing. The moving blades of the primary compressor and the primary low-pressure turbine are fixedly arranged on the blade tip casing and have a gap between the moving blades and a hub. The moving blades of the primary low-pressure turbine are driven to rotate the blade tip casing by high-temperature and high-pressure gas during work, so that the primary compressor is driven to work.

[0048] The specific fuel consumption and unit thrust of the high-bypass-ratio turbofan engine power system based on the rotating casing are calculated by zero-dimensional calculation with a commercially available CFM56-5C2 engine as a comparative example, wherein the design conditions are that the flight height is 10.7 km, the flight Mach number is 0.8, the fan pressure ratio is 2.24, the channel ratio is 6.6, and the third channel ratio is 2.0, and the results are shown in Table 1.

[0049] Table 1: Performance index comparison of different engine power systems

[0050]

[0051]

[0052] As shown in Table 1, the specific fuel consumption of the high-bypass-ratio turbofan engine power system based on the rotating casing is lower than that of the CFM56-5C2 engine, which indicates that the engine power system of the application can realize lower energy consumption under the same environmental conditions, and the flight cost is reduced.

[0053] In addition, the unit thrust of the engine power system of the application is higher than that of the CFM56-5C2 engine, and the efficiency of the engine is improved. In combination with all indexes, the high-bypass-ratio turbofan engine power system based on the rotating casing is a product with more superior performance than a traditional turbofan engine power system.

[0054] Those skilled in the art can understand that the above description is only preferred embodiments of the present application, and the features described in various embodiments of the present disclosure and / or claims can be combined or combined, even if such combination or combination is not explicitly described in the present disclosure. It is not intended to limit the present application, although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art can modify the technical solutions described in the foregoing embodiments or make equivalent replacement for part of the technical features, and any modification, equivalent replacement, improvement, etc. within the spirit and principle of the present application shall be included in the protection scope of the present application.

[0055] Although preferred embodiments of the present application have been described, those skilled in the art can make further changes and modifications to these embodiments once they know the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications falling within the scope of the present application. Obviously, those skilled in the art can make various modifications and variations to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalent technologies, the present application also intends to include these modifications and variations.

Claims

1. A high-bypass-ratio turbofan engine power system based on a rotating casing, characterized in that, The large-bypass-ratio turbofan engine power system based on rotating casing comprises a fan (1), a primary compressor (2), a rotating casing (3), a low-pressure compressor (5), a high-pressure compressor (6), a combustion chamber (7), a high-pressure turbine (8), a low-pressure turbine (9), a primary low-pressure turbine (4), an exhaust nozzle (10), a stationary casing inner end face (11) and a stationary casing outer end face (12). The fan (1) is arranged inside the stationary casing outer end face (12), one outlet end of the fan (1) is communicated with the outer channel, and the other outlet end is communicated with the inlet end of the low-pressure compressor (5). The low-pressure compressor (5), the high-pressure compressor (6), the combustion chamber (7), the high-pressure turbine (8), the low-pressure turbine (9), the primary low-pressure turbine (4) and the exhaust nozzle (10) are arranged in sequence in the axial direction. The primary compressor (2) and the primary low-pressure turbine (4) are provided with tip casing, and the tip casing is fixedly connected with the rotating casing (3). The fan (1) is connected with the low-pressure compressor (5) and the low-pressure turbine (9) through a transmission shaft. The high-pressure compressor (6) is connected with the high-pressure turbine (8) through a transmission shaft. The combustion chamber (7) is fixedly arranged inside the stationary casing inner end face (11), and the inlet of the exhaust nozzle (10) is connected with the outlet of the primary low-pressure turbine (4).

2. The high-bypass ratio, rotating casing-based turbofan engine power system according to Claim 1, wherein, The stationary casing outer end face (12) and the rotating casing (3) are provided with a third channel, the primary compressor (2) is arranged on the third channel, and the primary low-pressure turbine (4) is arranged inside the stationary casing inner end face (11).

3. The high-bypass ratio, rotating casing-based turbofan engine power system according to Claim 1, wherein, The rotating casing (3) is driven to rotate by the primary low-pressure turbine (4).

4. The high-bypass ratio, rotating casing-based turbofan engine power system according to Claim 1, wherein, The fan (1) is arranged in the axial direction and in front of the stationary casing inner end face (11), and the low-pressure compressor (5), the high-pressure compressor (6), the combustion chamber (7), the high-pressure turbine (8), the low-pressure turbine (9), the primary low-pressure turbine (4) and the exhaust nozzle (10) are arranged inside the stationary casing inner end face (11).

5. The high-bypass ratio, rotating casing-based turbofan engine power system according to Claim 1, wherein, The fan (1), the primary compressor (2), the low-pressure compressor (5), the high-pressure compressor (6), the combustion chamber (7), the high-pressure turbine (8), the low-pressure turbine (9), the primary low-pressure turbine (4), the exhaust nozzle (10), the stationary casing inner end face (11) and the stationary casing outer end face (12) are arranged inside the rotating casing (3).

6. The high-bypass ratio, rotating casing-based turbofan engine power system according to Claim 1, wherein, The system further comprises a step of optimizing the ratio of the diameter of the rotating casing (3) to the diameter of the fan (1).

7. The high-bypass ratio, rotating casing-based turbofan engine power system according to Claim 6, wherein, The ratio of the diameter of the rotating casing (3) to the diameter of the fan (1) is 0.1 to 0.

4.

8. The high-bypass ratio, rotor casing based turbofan engine power system according to Claim 1, wherein, The primary compressor (2) further comprises a step of adjusting power for different flight conditions.

9. A method for designing a high-bypass-ratio turbofan engine power system based on a rotating casing according to any one of claims 1 to 8, characterized in that, The design method comprises the following steps: designing a working condition parameter, calculating the specific fuel consumption and unit thrust of the large-bypass-ratio turbofan engine power system based on rotating casing, and obtaining the optimal specific fuel consumption and unit thrust by comparing the specific fuel consumption and unit thrust calculated by the large-bypass-ratio turbofan engine power system and other engine power systems.

10. The method of designing a high bypass ratio turbofan engine powered system based on a rotating nacelle according to claim 9, characterized in that, The working condition parameter comprises flight altitude, fan pressure ratio and third channel ratio.

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