Intermediary support engine low pressure turbine rotor blade dynamic stress measurement device and method

Abstract

The application relates to the technical field of high-efficiency cooling of an aero-engine lubricating oil system, and discloses a middle support engine low-pressure turbine rotor blade dynamic stress measuring device and method, 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 telemetry transceiving device, and can guide cooling air into a working cavity by using a gas supply device as a gas source and a gas guiding assembly, so that the high-temperature air flow outside an end cover can be isolated, the interference of the high-temperature air flow outside the end cover on data transmission of the telemetry transceiving device is reduced, and the accuracy of the transmission data is ensured.

Description

Technical Field

[0001] This invention relates to the field of high-efficiency cooling technology for aero-engine lubricating oil systems, and discloses a device and method for measuring the dynamic stress of low-pressure turbine rotor blades in an intermediate-supported engine. Background Technology

[0002] Low-pressure turbine blades in aero-engines experience high temperature and aerodynamic loads in harsh environments, leading to occasional blade cracking and fracture failures during development and operation. Under actual engine operating conditions, the rigidity of the connection between the blades and the disk, along with the combined effects of centrifugal force, thermal stress, and aerodynamic forces, causes a difference between the dynamic frequency (natural frequency) of the rotating blades and their static frequency in the non-rotating state. The intermediate support of the low-pressure turbine rotor in the aero-engine, supported by bearings, further exacerbates the load on the low-pressure turbine rotor blades due to the different rotational speeds of the high-pressure and low-pressure turbines and the coupling effect. Therefore, dynamic stress measurements of the low-pressure turbine rotor blades are essential during engine development and troubleshooting. This is used to verify design analysis and model calculation results, identify structural weaknesses in the blades, and implement design improvements to enhance their lifespan and reliability.

[0003] In the context of an aero-engine with intermediate supports, the complex mutual support structure of the high- and low-pressure turbine rotors further increases the difficulty of testing and modification. The dynamic stress measurement signal transmission line of the low-pressure turbine rotor 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 components and then lead the signal out of the engine via test lines. However, the outlet temperature of the low-pressure turbine in an aero-engine can reach 950℃, and the radiation from the afterburner further increases the ambient temperature. To ensure the safe operation of the telemetry device, the telemetry system needs to be cooled; existing telemetry systems have insufficient cooling efficiency. Summary of the Invention

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

[0005] To achieve the above-mentioned technical effects, the technical solution adopted by the present invention is as follows:

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

[0007] A telemetry transceiver device, comprising a transmitter and a receiver, wherein the transmitter is used to wirelessly transmit data collected by the rotor blade dynamic stress measurement component to the receiver, and the receiver is used to transmit the received signal to a host computer.

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

[0009] A bracket is fixed to a turbine support housing, and a receiving end is fixed to the bracket, with the receiving end facing the transmitting end.

[0010] An end cap is fixed to the turbine support housing and is coaxially arranged with the low-pressure turbine rotor. The axial position of the end cap and the axial position of the transmitting end are respectively located on both sides of the receiving end.

[0011] A graphite mounting base is provided, with one end fixed to the inner wall of the turbine support casing and the other end extending to a position near the outer wall of the telemetry mounting shaft; a graphite sealing assembly is provided between the graphite mounting base and the telemetry mounting shaft; the graphite mounting base 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, with the telemetry transceiver and the bracket both located in the working cavity;

[0012] Air intake assembly is used to guide cooling airflow into the working chamber;

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

[0014] Furthermore, the support has airflow holes, which are distributed circumferentially on the support.

[0015] Furthermore, an isolation cover is also 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, with the first chamber located near the bracket.

[0016] Furthermore, the air intake assembly includes a first air intake conduit and a second air intake conduit, wherein the first air intake conduit is connected to a first chamber and the second air intake conduit is connected to a 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 provided on the telemetry mounting shaft to guide part of the lubricating oil to a position close to the high-pressure turbine support bearing.

[0018] To achieve the above-mentioned technical effects, the present invention also provides a method for measuring the dynamic stress of low-pressure turbine rotor blades in an intermediate-supported engine. This method is based on the aforementioned dynamic stress measuring device for low-pressure turbine rotor blades in an intermediate-supported engine, and includes:

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

[0020] The dynamic stress signal of the blade is collected in real time using a rotor blade dynamic stress measurement component and transmitted to the host computer through a telemetry transceiver.

[0021] Furthermore, an isolation cover is also 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. The first chamber is located near the bracket. The air bleed assembly includes a first air bleed duct and a second air bleed duct. 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: Based on the operating environment of the telemetry transceiver, the present invention utilizes a graphite mounting base and a graphite sealing assembly to isolate an oil-free installation space from the lubricating oil cavity, and uses an air supply device as an air source. Cooling airflow can be introduced into the working cavity through the air duct assembly, which can isolate the high-temperature airflow outside the end cover, thereby reducing the interference of the high-temperature airflow outside the end cover on the data transmission of the telemetry transceiver and ensuring the accuracy of the transmitted data. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the dynamic stress measurement device for the low-pressure turbine rotor blades of the engine with intermediate support in the embodiment.

[0024] The components include: 1. Low-pressure turbine rotor; 2. First bearing; 3. Turbine support casing; 4. Transmitter; 5. Receiver; 6. Dynamic stress measurement assembly; 7. Telemetry mounting shaft; 8. Bracket; 9. End cap; 10. Graphite mounting base; 11. Graphite sealing assembly; 12. Lubricating oil chamber; 13. Oil guiding assembly; 14. Airflow 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 Implementation

[0025] The present invention will now be described in further detail with reference to the embodiments and accompanying drawings. However, this should not be construed as limiting the scope of the above-described subject matter of the present invention to the following embodiments; all technologies implemented based on the content of the present invention fall within the scope of the present invention.

[0026] Example

[0027] See Figure 1A dynamic stress measuring device for low-pressure turbine rotor blades 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, and the measuring device includes:

[0028] The telemetry transceiver includes a transmitter 4 and a receiver 5. The transmitter 4 is used to wirelessly transmit the data collected by the rotor blade dynamic stress measurement component 6 to the receiver 5. The receiver 5 is used to transmit the received signal to the host computer.

[0029] Telemetry mounting 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 mounting shaft 7;

[0030] A bracket 8 is fixed to the turbine support housing 3, and a receiving end 5 is fixed to the bracket 8, with the receiving end 5 facing the transmitting end 4.

[0031] End cap 9, which is fixed on the turbine support housing 3 and is coaxially arranged with the low-pressure turbine rotor 1. The axial position of the end cap 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 base 10 is provided, with one end fixed to the inner wall of the turbine support casing 3 and the other end extending 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 base 10 and the telemetry mounting shaft 7; the graphite mounting base 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 chamber 12 and a working chamber, and the telemetry transceiver and the bracket 8 are both located in the working chamber;

[0033] Air intake assembly is used to guide cooling airflow into the working chamber;

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

[0035] In this embodiment, based on the operating environment of the telemetry transceiver, an oil-free installation space is isolated from the lubricating oil chamber 12 using the graphite mounting base 10 and the graphite sealing assembly 11. An air supply device is used as the air source, and cooling airflow is introduced into the working chamber through the air duct assembly. This isolates 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 telemetry transceiver and ensuring the accuracy of the transmitted data. The measuring device in this invention ensures that both the telemetry system's operating conditions and the lubricating oil system function normally. It has a compact structure, reliable test data, good economic benefits, and significant practical engineering application value.

[0036] In this embodiment, the support 8 is provided with airflow holes 14, which are distributed circumferentially on the support 8. The cooling airflow flows through the airflow holes 14 on the support 8 to the telemetry transceiver and the graphite sealing assembly 11, which not only cools the telemetry transceiver but also seals and cools the graphite sealing assembly 11.

[0037] In this embodiment, 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 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. After the isolation cover 15 divides the working chamber, the second chamber 17 alone isolates the high-temperature airflow outside the end cover 9, while the inner first chamber 16 serves the dual purpose of heat insulation and sealing.

[0038] In this embodiment, the air intake assembly includes a first air intake conduit 18 and a second air intake conduit 19. The first air intake conduit 18 is connected to the first chamber 16, and the second air intake conduit 19 is connected to the second chamber 17. Based on the isolation cover 15, the first air intake conduit 18 and the second air intake conduit 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 can be connected to a conventional air supply device via the first air intake conduit 18 to provide sealing airflow to seal the graphite sealing assembly 11; the second chamber 17 can be connected to a cold air source via the second air intake conduit 19. The cooling airflow flowing into the second chamber 17 isolates and cools the high-temperature airflow outside the end cover 9, further improving the heat insulation effect of the telemetry transceiver, ensuring a stable operating environment temperature for the telemetry transceiver, and reducing the likelihood of data transmission distortion.

[0039] In this embodiment, a high-pressure turbine support assembly 20 is coaxially disposed on the outer wall of the low-pressure turbine rotor 1, and a high-pressure turbine support bearing 21 is disposed between the high-pressure turbine support assembly 20 and the low-pressure turbine rotor 1; an oil guide groove 22 is disposed on the telemetry mounting shaft 7, which is used to guide a portion 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 generates 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 assembly and an exhaust assembly, but since both of these structures are conventional structures, they will not be described or illustrated in detail in this embodiment.

[0041] The above are merely 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 within the protection scope of the present invention.

Claims

1. A dynamic stress measuring device for blades of a low-pressure turbine rotor (1) of an engine with intermediate support, 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 includes: The telemetry transceiver includes a transmitter (4) and a receiver (5). The transmitter (4) is used to wirelessly transmit the data collected by the rotor blade dynamic stress measurement component (6) to the receiver (5). The receiver (5) is used to transmit the received signal to the host computer. Telemetry mounting 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 mounting shaft (7); A bracket (8) is fixed on a turbine support housing (3), and a receiver (5) is fixed on the bracket (8), with the receiver (5) facing the transmitter (4). End cap (9), the end cap (9) is fixed on the turbine support casing (3), and the end cap (9) is coaxially arranged with the low-pressure turbine rotor (1), and the axial position of the end cap (9) and the axial position of the transmitting end (4) are respectively located on both sides of the receiving end (5). A graphite mounting base (10) is provided, with one end fixed to the inner wall of the turbine support casing (3) and the other end extending 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 base (10) and the telemetry mounting shaft (7); the graphite mounting base (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 chamber (12) and a working chamber, and the telemetry transceiver and the bracket (8) are both located in the working chamber; Air intake assembly is used to guide cooling airflow into the working chamber; The oil guiding assembly (13) is used to guide lubricating oil into the lubricating oil chamber (12); 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). The first chamber (16) is located near the bracket (8). The air intake assembly includes a first air intake conduit (18) and a second air intake conduit (19). The first air intake conduit (18) is connected to the first chamber (16), and the second air intake conduit (19) is connected to the second chamber (17). The first air intake conduit (18) is connected to a conventional air supply device to provide sealing airflow, and the second air intake conduit (19) is connected to a cold air source.

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

3. The dynamic stress measuring device for the blades of the low-pressure turbine rotor (1) of an engine with intermediate support 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 provided 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).

4. A method for measuring the dynamic stress of blades in a low-pressure turbine rotor (1) of an intermediate-supported engine, the method being based on the dynamic stress measuring device for blades in a low-pressure turbine rotor (1) of an intermediate-supported engine as described 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); The rotor blade dynamic stress measurement component (6) is used to collect the blade dynamic stress signal in real time and transmit it to the host computer through the telemetry transceiver device.

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