Device and method for measuring dynamic stress of low-pressure turbine rotor blade of intermediate support engine

Abstract

The invention relates to the technical field of efficient cooling of an aero-engine lubricating oil system, and discloses a dynamic stress measuring device and method for a low-pressure turbine rotor blade of an intermediate support engine, which can isolate an oil-free mounting space from a lubricating oil cavity by using a graphite mounting seat and a graphite sealing assembly according to the use environment of a telemetering transceiving device. The air supply device is adopted as an air source, cooling airflow can be guided into the working cavity through the air guiding assembly, the effect of isolating high-temperature airflow on the outer side of the end cover can be achieved, interference of the high-temperature airflow on the outer side of the end cover on data transmission of the telemetering transceiving device is reduced, and the accuracy of data transmission is ensured.

Description

Technical Field

[0001] The invention relates to the technical field of efficient cooling of aero-engine lubricating oil systems, and discloses a device and a method for measuring dynamic stress of a low-pressure turbine rotor blade of an intermediate-supported engine. Background Art

[0002] The temperature load and aerodynamic load of the low-pressure turbine blades of aircraft engines are high, and the working environment is harsh. Blade cracks and fractures occur occasionally during the development and use process. Under the actual working state of the engine, due to the connection rigidity between the working blades and the disk, and the combined effects of centrifugal force, thermal stress and aerodynamic force on the blades, the dynamic frequency (self-vibration frequency) of the blades in the rotating state is different from the static frequency in the non-rotating state. The low-pressure turbine rotor and the high-pressure turbine rotor of the intermediate-supported aircraft engine are supported by bearings. The high-pressure turbine rotor and the low-pressure turbine have different rotation speeds, and the coupling effect further aggravates the load on the low-pressure turbine rotor blades. Therefore, during the engine development and troubleshooting process, it is necessary to measure the dynamic stress of the low-pressure turbine rotor blades to verify the design analysis and model calculation results, find out the weak points of the blade structure, improve the design, and improve its life and reliability.

[0003] In the environment of an intermediate-supported aircraft engine, the complexity of the mutual support structure of the high- and low-pressure turbine rotors further increases the difficulty of testing and modification. The transmission line of the dynamic stress measurement signal of the low-pressure turbine rotor of the aircraft engine cannot be directly led out of the engine to the PC for data analysis. A telemetry system is required to transmit the signal to the stator component and then lead the signal out of the engine through the test line. The outlet temperature of the low-pressure turbine of an aircraft engine can reach 950°C, and the radiation effect of the afterburner end further increases its ambient temperature. In order to ensure the safe operation of the telemetry device, the telemetry system needs to be cooled, and the existing telemetry system has poor cooling efficiency. Summary of the invention

[0004] The purpose of the present invention is to provide a device and method for measuring the dynamic stress of a low-pressure turbine rotor blade of an intermediate support engine, which can reduce the interference of the high-temperature airflow outside the end cover on the data transmission of a telemetry transceiver and ensure the accuracy of the transmitted data.

[0005] In order to achieve the above technical effects, the technical solution adopted by the present invention is:

[0006] A device for measuring dynamic stress of a low-pressure turbine rotor blade of an intermediate support engine, wherein the low-pressure turbine rotor is mounted on a turbine support casing through a first bearing, and the measuring device comprises:

[0007] A telemetering transceiver, the telemetering transceiver comprising a transmitter and a receiver, the transmitter being used to wirelessly transmit data collected by the rotor blade dynamic stress measurement assembly to the receiver, and the receiver being used to transmit received signals to a host computer;

[0008] A telemetry installation shaft, wherein the telemetry installation shaft is coaxially fixed in the inner cavity of the low-pressure turbine rotor, and the transmitting end is fixed on the telemetry installation shaft;

[0009] A bracket, wherein the bracket is fixed on the turbine support casing, the receiving end is fixed on the bracket, and the receiving end is arranged opposite to the transmitting end;

[0010] An end cover, wherein the end cover is fixed on the turbine support casing, and the end cover is coaxially arranged with the low-pressure turbine rotor, and the axial position of the end cover and the axial position of the transmitting end are respectively located on both sides of the receiving end;

[0011] A graphite mounting seat, one end of which is fixed to the inner wall of the turbine support casing, and the other end of which extends to a position close to the outer wall of the telemetry mounting shaft; a graphite sealing assembly is arranged between the graphite mounting seat and the telemetry mounting shaft; the graphite mounting seat divides the cavity formed by the low-pressure turbine rotor, the turbine support casing and the end cover into a lubricating oil cavity and a working cavity, and the telemetry transceiver and the bracket are both located in the working cavity;

[0012] An air bleed assembly, used to introduce cooling air flow into the working chamber;

[0013] The oil guide assembly is used to guide the lubricating oil into the lubricating oil cavity.

[0014] Furthermore, the bracket is provided with air flow holes, and the air flow holes are distributed circumferentially on the bracket.

[0015] Furthermore, an isolation cover is installed on the turbine support casing, the isolation cover is located between the bracket and the end cover, and the isolation cover is coaxially arranged with the low-pressure turbine rotor; the isolation cover divides the working chamber into a first chamber and a second chamber, and the first chamber is located close to the bracket.

[0016] Furthermore, the air bleed assembly includes a first air bleed duct and a second air bleed duct, the first air bleed duct is communicated with the first chamber, and the second air bleed duct is communicated with the second chamber.

[0017] Furthermore, a high-pressure turbine support assembly is coaxially arranged on the outer wall of the low-pressure turbine rotor, and a high-pressure turbine support bearing is arranged between the high-pressure turbine support assembly and the low-pressure turbine rotor; an oil guide groove is arranged on the telemetry mounting shaft for directing part of the lubricating oil to a position close to the high-pressure turbine support bearing.

[0018] In order to achieve the above technical effects, the present invention also provides a method for measuring the dynamic stress of a low-pressure turbine rotor blade of an intermediate support engine. The method is based on the device for measuring the dynamic stress of a low-pressure turbine rotor blade of an intermediate support engine, and comprises:

[0019] During the rotation of the low-pressure turbine rotor, an air bleed assembly is used to provide air flow into the working chamber, and an oil guide assembly is used to introduce lubricating oil into the lubricating oil chamber;

[0020] The rotor blade dynamic stress measurement component is used to collect blade dynamic stress signals in real time and transmit them to the host computer through a telemetry transceiver.

[0021] Furthermore, an isolation cover is also installed on the turbine support casing, and the isolation cover is located between the bracket and the end cover, and the isolation cover is coaxially arranged with the low-pressure turbine rotor; the isolation cover divides the working chamber into a first chamber and a second chamber, and the first chamber is located near the bracket; the air bleed assembly includes a first air bleed duct and a second air bleed duct, and the first air bleed duct is used to independently introduce airflow into the first chamber, and the second air bleed duct is used to independently introduce cooling airflow into the second chamber.

[0022] Compared with the prior art, the beneficial effects of the present invention are as follows: according to the use environment of the telemetry transceiver, the present invention utilizes a graphite mounting seat and a graphite sealing assembly to isolate an oil-free installation space from the lubricating oil cavity, and adopts an air supply device as an air source. A cooling airflow can be introduced into the working cavity through an air bleed assembly, which can isolate the high-temperature airflow on the outside of the end cover, thereby reducing the interference of the high-temperature airflow on the outside of the end cover with the data transmission of the telemetry transceiver, thereby ensuring the accuracy of the transmitted data. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a schematic structural diagram of a device for measuring dynamic stress of a low-pressure turbine rotor blade of an intermediate support engine in an embodiment;

[0024] Among them, 1. low-pressure turbine rotor; 2. first bearing; 3. turbine support casing; 4. transmitting end; 5. receiving end; 6. dynamic stress measurement assembly; 7. telemetry mounting shaft; 8. bracket; 9. end cover; 10. graphite mounting seat; 11. graphite sealing assembly; 12. lubricating oil cavity; 13. oil guide assembly; 14. air flow hole; 15. isolation cover; 16. first chamber; 17. second chamber; 18. first air duct; 19. second air duct; 20. high-pressure turbine support assembly; 21. high-pressure turbine support bearing; 22. oil guide groove. DETAILED DESCRIPTION

[0025] The present invention is further described in detail below in conjunction with the embodiments and drawings. However, it should not be understood that the scope of the above subject matter of the present invention is limited to the following embodiments, and all technologies realized based on the content of the present invention belong to the scope of the present invention.

[0026] Example

[0027] See also Figure 1, a device for measuring dynamic stress of a low-pressure turbine rotor blade of an intermediate support engine, wherein the low-pressure turbine rotor 1 is mounted on a turbine support casing 3 through a first bearing 2, and the measuring device comprises:

[0028] A telemetering transceiver, the telemetering transceiver comprising a transmitter 4 and a receiver 5, the transmitter 4 being used to wirelessly transmit data collected by a rotor blade dynamic stress measurement assembly 6 to the receiver 5, and the receiver 5 being used to transmit received signals to a host computer;

[0029] A telemetry installation shaft 7, wherein the telemetry installation shaft 7 is coaxially fixed in the inner cavity of the low-pressure turbine rotor 1, and the transmitting end 4 is fixed on the telemetry installation shaft 7;

[0030] A bracket 8, wherein the bracket 8 is fixed on the turbine support casing 3, the receiving end 5 is fixed on the bracket 8, and the receiving end 5 is arranged opposite to the transmitting end 4;

[0031] An end cover 9, wherein the end cover 9 is fixed on the turbine support casing 3, and the end cover 9 is coaxially arranged with the low-pressure turbine rotor 1, and the axial position of the end cover 9 and the axial position of the transmitting end 4 are respectively located on both sides of the receiving end 5;

[0032] A graphite mounting seat 10, one end of which is fixed to the inner wall of the turbine support casing 3, and the other end of which extends to a position close to the outer wall of the telemetry mounting shaft 7; a graphite sealing assembly 11 is provided between the graphite mounting seat 10 and the telemetry mounting shaft 7; the graphite mounting seat 10 divides the cavity formed by the low-pressure turbine rotor 1, the turbine support casing 3 and the end cover 9 into a lubricating oil cavity 12 and a working cavity, and the telemetry transceiver and the bracket 8 are both located in the working cavity;

[0033] An air bleed assembly, used to introduce cooling air flow into the working chamber;

[0034] The oil guide assembly 13 is used to guide the lubricating oil into the lubricating oil cavity 12 .

[0035] In this embodiment, according to the use environment of the telemetering transceiver, the graphite mounting seat 10 and the graphite sealing assembly 11 are used to isolate the oil-free installation space from the lubricating oil cavity 12, and the air supply device is used as the air source. The cooling airflow can be introduced into the working cavity through the air bleed assembly, which can play the role of isolating the high-temperature airflow outside the end cover 9, thereby reducing the interference of the high-temperature airflow outside the end cover 9 on the data transmission of the telemetering transceiver, and ensuring the accuracy of the transmitted data. The measuring device in the present invention not only ensures that the working conditions of the telemetering system meet the requirements, but also meets the normal operation of the lubricating oil system. It has a compact structure, reliable test data, good economic benefits and great practical engineering application value.

[0036] In this embodiment, the bracket 8 is provided with air flow holes 14, and the air flow holes 14 are circumferentially distributed on the bracket 8; the cooling air flow flows to the telemetry transceiver and the graphite sealing assembly 11 through the air flow holes 14 on the bracket 8, which can not only cool the telemetry transceiver, but also seal and cool the graphite sealing assembly 11.

[0037] In this embodiment, an isolation cover 15 is also installed on the turbine support casing 3, and the isolation cover 15 is located between the bracket 8 and the end cover 9, and the isolation cover 15 is coaxially arranged with the low-pressure turbine rotor 1; the isolation cover 15 divides the working chamber into a first chamber 16 and a second chamber 17, and the first chamber 16 is located near the bracket 8. After the isolation cover 15 divides the working chamber, the second chamber 17 is used alone to isolate the high-temperature airflow outside the end cover 9, and the first chamber 16 inside plays the dual role of heat insulation and sealing.

[0038] In this embodiment, the air bleed assembly includes a first air bleed duct 18 and a second air bleed duct 19, wherein the first air bleed duct 18 is connected to the first chamber 16, and the second air bleed duct 19 is connected to the second chamber 17. On the basis of setting the isolation cover 15, the first air bleed duct 18 and the second air bleed duct 19 can be used to independently supply air to the first chamber 16 and the second chamber 17, respectively. For example, the first chamber 16 uses the first air bleed duct 18 to connect to a conventional air supply device to provide a sealing airflow to seal the graphite sealing assembly 11; the second chamber 17 uses the second air bleed duct 19 to connect to a cold air source, and the high-temperature airflow outside the end cover 9 is isolated and cooled by the cooling airflow flowing into the second chamber 17, thereby further improving the heat insulation effect of the telemetry transceiver, ensuring that the working environment temperature of the telemetry transceiver is stable and that the problem of transmission data distortion is not easy to occur.

[0039] In this embodiment, a high-pressure turbine support assembly 20 is coaxially arranged on the outer wall of the low-pressure turbine rotor 1, and a high-pressure turbine support bearing 21 is arranged between the high-pressure turbine support assembly 20 and the low-pressure turbine rotor 1; an oil guide groove 22 is arranged on the telemetry installation shaft 7, which is used to guide part of the lubricating oil to a position close to the high-pressure turbine support bearing 21. During the rotation of the low-pressure turbine rotor 1, the centrifugal force of the lubricating oil produces an oil-throwing effect, thereby achieving lubrication and cooling of the high-pressure turbine support bearing 21.

[0040] It should be noted that the measuring device in this embodiment also includes an oil return component and an exhaust component, but since these two structures are conventional structures, they will not be described or illustrated in detail in this embodiment.

[0041] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A device for measuring blade dynamic stress of a low-pressure turbine rotor (1) of an intermediate support engine, wherein the low-pressure turbine rotor (1) is mounted on a turbine support casing (3) via a first bearing (2), characterized in that: The measuring device comprises: A telemetry transceiver device, the telemetry transceiver device comprising a transmitter (4) and a receiver (5), the transmitter (4) being used to wirelessly transmit data collected by a rotor blade dynamic stress measurement component (6) to the receiver (5), and the receiver (5) being used to transmit received signals to a host computer; A telemetry installation shaft (7), the telemetry installation shaft (7) being coaxially fixed in the inner cavity of the low-pressure turbine rotor (1), and the transmitting end (4) being fixed on the telemetry installation shaft (7); A bracket (8), wherein the bracket (8) is fixed on the turbine support casing (3), the receiving end (5) is fixed on the bracket (8), and the receiving end (5) is arranged opposite to the transmitting end (4); An end cover (9), the end cover (9) being fixed on the turbine support casing (3), the end cover (9) being coaxially arranged with the low-pressure turbine rotor (1), and the axial position of the end cover (9) and the axial position of the transmitting end (4) being respectively located on both sides of the receiving end (5); A graphite mounting seat (10), one end of the graphite mounting seat (10) is fixed to the inner wall of the turbine support casing (3), and the other end extends to a position close to the outer wall of the telemetry mounting shaft (7); a graphite sealing assembly (11) is arranged between the graphite mounting seat (10) and the telemetry mounting shaft (7); the graphite mounting seat (10) divides the cavity formed by the low-pressure turbine rotor (1), the turbine support casing (3) and the end cover (9) into a lubricating oil cavity (12) and a working cavity, and the telemetry transceiver and the bracket (8) are both located in the working cavity; An air bleed assembly, used to introduce cooling air flow into the working chamber; The oil guide assembly (13) is used to guide the lubricating oil into the lubricating oil cavity (12).

2. The device for measuring blade dynamic stress of a low-pressure turbine rotor (1) of an intermediate support engine according to claim 1, characterized in that: The support (8) is provided with air flow holes (14), and the air flow holes (14) are distributed circumferentially on the support (8).

3. The device for measuring blade dynamic stress of a low-pressure turbine rotor (1) of an intermediate support engine according to claim 1, characterized in that: An isolation cover (15) is also installed on the turbine support casing (3), the isolation cover (15) is located between the bracket (8) and the end cover (9), and the isolation cover (15) is coaxially arranged with the low-pressure turbine rotor (1); the isolation cover (15) divides the working chamber into a first chamber (16) and a second chamber (17), and the first chamber (16) is located near the bracket (8).

4. The device for measuring blade dynamic stress of a low-pressure turbine rotor (1) of an intermediate support engine according to claim 3, characterized in that: The air bleed assembly comprises a first air bleed duct (18) and a second air bleed duct (19), wherein the first air bleed duct (18) is communicated with the first chamber (16), and the second air bleed duct (19) is communicated with the second chamber (17).

5. The device for measuring blade dynamic stress of a low-pressure turbine rotor (1) of an intermediate support engine according to claim 1, characterized in that: A high-pressure turbine support assembly (20) is coaxially arranged on the outer wall of the low-pressure turbine rotor (1), and a high-pressure turbine support bearing (21) is arranged between the high-pressure turbine support assembly (20) and the low-pressure turbine rotor (1); an oil guide groove (22) is arranged on the telemetry mounting shaft (7) for guiding part of the lubricating oil to a position close to the high-pressure turbine support bearing (21).

6. A method for measuring the dynamic stress of a blade of a low-pressure turbine rotor (1) of an intermediate support engine, the method being based on the device for measuring the dynamic stress of a blade of a low-pressure turbine rotor (1) of an intermediate support engine as claimed in claim 1, characterized in that: include: During the rotation of the low-pressure turbine rotor (1), an air bleed assembly is used to provide airflow into the working chamber, and an oil guide assembly (13) is used to introduce lubricating oil into the lubricating oil chamber (12); A rotor blade dynamic stress measurement component (6) is used to collect blade dynamic stress signals in real time, and transmit the signals to a host computer via a telemetry transceiver.

7. The method for measuring the dynamic stress of the blades of the low-pressure turbine rotor (1) of the intermediate support engine according to claim 6, characterized in that: The turbine support casing (3) is also provided with an isolation cover (15), the isolation cover (15) is located between the bracket (8) and the end cover (9), and the isolation cover (15) is coaxially arranged with the low-pressure turbine rotor (1); the isolation cover (15) divides the working chamber into a first chamber (16) and a second chamber (17), the first chamber (16) is located near the bracket (8); the air bleed assembly comprises a first air bleed duct (18) and a second air bleed duct (19), the first air bleed duct (18) is used to independently introduce airflow into the first chamber (16), and the second air bleed duct (19) is used to independently introduce cooling airflow into the second chamber (17).

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