WO2026020342A1 - 一种借鉴微波传输线理论的航空发动机转子界面刚度原位超声检测方法与装置 - Google Patents

一种借鉴微波传输线理论的航空发动机转子界面刚度原位超声检测方法与装置

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Publication number
WO2026020342A1
WO2026020342A1 PCT/CN2024/107162 CN2024107162W WO2026020342A1 WO 2026020342 A1 WO2026020342 A1 WO 2026020342A1 CN 2024107162 W CN2024107162 W CN 2024107162W WO 2026020342 A1 WO2026020342 A1 WO 2026020342A1
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WIPO (PCT)
Prior art keywords
probe
servo motor
ultrasonic probe
turntable
ultrasonic
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Pending
Application number
PCT/CN2024/107162
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English (en)
French (fr)
Inventor
袁博
韩泽生
王英全
赵家赫
夏泽明
孙清超
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Dalian University of Technology
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Dalian University of Technology
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Priority to PCT/CN2024/107162 priority Critical patent/WO2026020342A1/zh
Priority to US19/240,641 priority patent/US20250383322A1/en
Publication of WO2026020342A1 publication Critical patent/WO2026020342A1/zh
Pending legal-status Critical Current
Anticipated expiration legal-status Critical

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Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N29/00—Investigating or analysing materials by the use of ultrasonic, sonic or infrasonic waves; Visualisation of the interior of objects by transmitting ultrasonic or sonic waves through the object
    • G01N29/04—Analysing solids
    • G01N29/09—Analysing solids by measuring mechanical or acoustic impedance
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N29/00—Investigating or analysing materials by the use of ultrasonic, sonic or infrasonic waves; Visualisation of the interior of objects by transmitting ultrasonic or sonic waves through the object
    • G01N29/22—Details, e.g. general constructional or apparatus details
    • G01N29/26—Arrangements for orientation or scanning by relative movement of the head and the sensor
    • G01N29/265—Arrangements for orientation or scanning by relative movement of the head and the sensor by moving the sensor relative to a stationary material
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N2291/00—Indexing codes associated with group G01N29/00
    • G01N2291/26—Scanned objects
    • G01N2291/269—Various geometry objects
    • G01N2291/2693—Rotor or turbine parts

Definitions

  • This invention belongs to the field of interface stiffness testing technology, and relates to an in-situ ultrasonic testing method and device for interface stiffness of aero-engine rotors based on microwave transmission line theory.
  • ultrasonic measurement technology Compared with other measurement methods, ultrasonic measurement technology has the advantages of being unrestricted by material properties, having strong in-situ measurement capabilities, and high sensitivity to interface measurements, thus meeting the basic requirements for in-situ measurement of aero-engine rotors. Of particular importance is the robustness of the interface stiffness measurement method and its operability within the confined space of the aero-engine rotor.
  • Li Rui's portable ring stiffness testing device and operating method require placing the pipe to be tested on a testing platform.
  • testing process requirements testing needs to be carried out at a specific workstation, increasing the difficulty of testing the interface stiffness of aero-engine rotors.
  • Jiang Chunyu's ultrasonic testing-based non-destructive testing device for composite materials and related components uses an open testing device.
  • the internal space of the compressor drum disk is small and the operating space is limited, making it difficult for existing open testing equipment to enter, and making it difficult to perform related interface stiffness testing on existing rotors.
  • Mu Xiaokai's interface stiffness detection device based on solid coupling does not consider the uncertainty of the sensing boundary parameters.
  • the uncertainty of the sensing boundary parameters during the detection process can easily lead to a decrease in measurement performance, limiting the application of interface stiffness measurement.
  • the purpose of this invention is to solve the problem of difficult interface stiffness testing in aero-engines, and to provide an in-situ ultrasonic testing method and device for aero-engine rotor interface stiffness based on microwave transmission line theory.
  • This invention can reduce the randomness of sensing boundaries by utilizing microwave transmission line theory, enables interface stiffness testing in the confined space of an aero-engine, achieves good repeatability by using springs to provide pressure, and improves the coaxiality of the upper and lower probes by using a connecting cylinder to achieve synchronous rotation of the upper and lower structures.
  • An in-situ ultrasonic testing method for the interface stiffness of an aero-engine rotor utilizes an in-situ ultrasonic testing device for the interface stiffness of an aero-engine rotor.
  • a fixing claw 2 is clamped onto the inner ring surface of the aero-engine; the upper ultrasonic probe 28 and the lower ultrasonic probe 36 are deployed, positioning them above and below the point to be tested, respectively; the upper ultrasonic probe 28 and the lower ultrasonic probe 36 are pressed tightly against the testing position by the mutual attraction between the electromagnet 12 and the adsorption cylinder 16; ultrasonic signals are emitted by the upper ultrasonic probe 28 and the lower ultrasonic probe 36 to obtain the transmission coefficient B1 , the upper surface reflection coefficient C12 , and the lower surface reflection coefficient C43 ; and the interface stiffness of the point to be tested is then calculated.
  • the TRDI expression for the interface stiffness of the test point is:
  • An in-situ ultrasonic testing device for the interface stiffness of an aero-engine rotor, drawing on microwave transmission line theory includes a device base 1, fixed jaws 2, positioning telescopic rods 3, fixed compression springs 4, an upper turntable end cover 5, an upper linear guide rail base 6, a lower turntable end cover 7, a lower linear guide rail base 8, an upper rolling bearing 9, and a lower rolling bearing.
  • Hollow connecting cylinder 11. Electromagnet; 12. Upper linear guide rail; 13. Upper linear slider; 14. Upper servo motor connecting plate; 15. Adsorption cylinder; 16. Adsorption cylinder seat; 17. Lower linear guide rail; 18. Lower linear slider; 19. Lower servo motor connecting plate; 20.
  • Upper servo motor rotating plate 24. Upper probe connecting rod fixing block; 25. Upper probe connecting rod; 26. Upper probe housing; 27. Upper ultrasonic probe; 28. Upper probe compression spring; 29. Lower servo motor; 30. Lower servo motor turntable; 31. Lower servo motor rotating plate; 32. Lower probe connecting rod fixing block; 33. Lower probe connecting rod; 34. Lower probe housing; 35. Lower ultrasonic probe; 36. Lower probe compression spring; 37.
  • the device base 1 and the hollow connecting cylinder 11 are concentric and are both hollow cylindrical structures.
  • Three positioning telescopic rods 3 are evenly distributed inside the device base 1 and the hollow connecting cylinder 11.
  • a fixing spring 4 is fitted on the positioning telescopic rod 3 located outside the hollow connecting cylinder 11.
  • the positioning telescopic rod 3 is positioned and fixed on the inner annular surface of the aero-engine under the action of the fixing spring 4.
  • the upper and lower ends of the device base 1 are connected to the upper turntable end cover 5 and the lower turntable end cover 7 respectively through the upper rolling bearing 9 and the lower rolling bearing 10.
  • the upper turntable end cover 5 and the lower turntable end cover 7 are connected through the hollow connecting cylinder 11 to achieve synchronous rotation and clamp the device base 1.
  • the upper turntable end cover 5 is connected to the upper linear guide rail base 6, the upper linear guide rail base 6 is connected to the upper linear guide rail 13, the lower turntable end cover 7 is connected to the lower linear guide rail base 8, and the lower linear guide rail base 8 is connected to the lower linear guide rail 18.
  • the electromagnet 12 is connected to the upper servo motor connecting plate 15, and the adsorption cylinder 16 is connected to the adsorption cylinder seat 17.
  • the upper servo motor 22 is connected to the lower servo motor connecting plate 20 via the adsorption cylinder 17; the mutual adsorption between the electromagnet 12 and the adsorption cylinder 16 provides clamping displacement for the ultrasonic probe; the upper servo motor 22 is connected to the upper servo motor connecting plate 15 via the upper servo motor adapter plate 21, the upper servo motor turntable 24 is connected to the upper servo motor 22 via the upper servo motor turntable 23, the upper probe connecting rod 26 is connected to the upper probe adapter plate 54 via the upper probe connecting rod fixing block 25, and the upper ultrasonic probe 28 is connected to the upper probe housing 27 and...
  • the upper probe compression spring 29 is connected to the upper probe connecting rod 26; the lower servo motor 30 is connected to the lower servo motor connecting plate 20, the lower servo motor turntable 32 is connected to the lower servo motor 30 through the lower servo motor turntable 31, the lower probe connecting rod 34 is connected to the lower probe adapter plate 63 through the lower probe connecting rod fixing block 33, and the lower ultrasonic probe 36 is connected to the lower probe connecting rod 34 through the lower probe compression spring 37 and the lower probe housing 35; the upper linear slider 14 is fixedly connected to the upper servo motor connecting plate 15. The movement of block 14 on the upper linear guide rail 13 drives the linear motion of the upper servo motor 22 and the upper ultrasonic probe 28.
  • the lower linear slider 19 is fixedly connected to the lower servo motor connecting plate 20.
  • the movement of the lower linear slider 19 on the lower linear guide rail 18 drives the linear motion of the lower servo motor 30 and the lower ultrasonic probe 36.
  • the upper servo motor 22 is connected to the upper servo motor turntable 23 through a spline.
  • the rotation of the output shaft of the upper servo motor 22 drives the rotation of the upper servo motor turntable 24 and the upper ultrasonic probe 28.
  • the lower servo motor 30 is connected to the lower servo motor turntable 31 through a spline.
  • the rotation of the output shaft of the lower servo motor 30 drives the rotation of the lower servo motor turntable 32 and the lower ultrasonic probe 36.
  • the upper ultrasonic probe 28 and the lower ultrasonic probe 36 are pressed against the upper probe housing 27 and the lower probe housing 35 by the action of the upper probe compression spring 29 and the lower probe compression spring 37, respectively.
  • the mutual attraction between the electromagnet 12 and the adsorption cylinder 16 provides clamping displacement for the upper ultrasonic probe 28 and the lower ultrasonic probe 36; under the clamping displacement generated by the electromagnet 12 and the adsorption cylinder 16, the upper ultrasonic probe 28 and the lower ultrasonic probe 36 are clamped by the upper probe compression spring 29 and the lower probe compression spring 37.
  • the electromagnet 12 is not energized and has no magnetism.
  • the upper servo motor connecting plate 15 and the lower servo motor connecting plate 20 are separated from each other, and the upper ultrasonic probe 28 and the lower ultrasonic probe 36 are in a retracted state. At this time, the upper ultrasonic probe 28 and the lower ultrasonic probe 36 have no clamping force.
  • the detection phase the upper ultrasonic probe 28 and the lower ultrasonic probe 36 are unfolded to the position to be tested.
  • the electromagnet 12 is energized and generates magnetism, attracting each other to the adsorption cylinder 16.
  • the upper servo motor connecting plate 15 and the lower servo motor connecting plate 20 move closer to each other, and the upper ultrasonic probe 28 and the lower ultrasonic probe 36 also move closer accordingly. Under the action of the upper probe compression spring 29 and the lower probe compression spring 37, a clamping force is generated, and the interface stiffness detection work is carried out.
  • the upper servo motor plate 24 and the lower servo motor plate 32 are initially in a retracted state. After the fixed claw 2 is positioned and fixed by the positioning telescopic rod 3 and the fixed compression spring 4, the upper servo motor plate 24 and the lower servo motor plate 32 are unfolded, so that the ultrasonic probe can be moved to the area to be tested.
  • the positioning telescopic rod 3 has a boss structure, which can be locked onto the inner plane of the device base 1 when retracted to prevent it from popping out under the action of the fixing spring 4, and matches the groove of the device base 1 when extended.
  • the locking claw 2 pops out in a specific posture and is fixed on the inner annular surface of the engine.
  • the beneficial effects of the present invention are as follows:
  • the present invention is characterized by its ability to perform interface stiffness testing in the confined space of an aero-engine, its ability to achieve good repeatability by using a spring rod to provide pressure, and its ability to achieve good stability by using the synchronous rotation of the upper and lower structures.
  • Figure 1 shows a schematic diagram of the similarities between ultrasonic and microwave transmission: (a) impedance mismatch in microwave transmission; (b) interfacial impedance discontinuity in ultrasonic propagation.
  • Figure 2 shows the transmission and reflection results of ultrasonic waves at a multi-layer contact interface.
  • Figure 3 shows the robustness comparison results between the proposed method and the traditional method: (a) statistical histogram of boundary parameters; (b) box plot of interface stiffness obtained by different methods;
  • Figure 4 is a schematic diagram of the overall structure of the detection device
  • Figure 5 is a side view of the detection device, showing the overall state of the detection device when it is retracted;
  • Figure 6 is a schematic diagram showing the internal connection structure of the detection device.
  • Lower linear slider 2 0 Lower servo connection plate; 21 Upper servo adapter plate; 22 Upper servo; 23 Upper servo turntable; 24 Upper servo turntable; 25 Upper probe connecting rod fixing block; 26 Upper probe connecting rod; 27 Upper probe housing; 28 Upper ultrasonic probe; 29 Upper probe compression spring; 30 Lower servo; 31 Lower servo turntable; 32 Lower servo turntable; 33 Lower probe connecting rod fixing block; 34 Lower probe connecting rod; 35 Lower probe housing; 36 Lower ultrasonic probe; 37 Lower probe compression spring.
  • Z1 and Z2 represent the acoustic impedance on both sides of the interface.
  • Microwaves also exhibit reflection characteristics when propagating in transmission lines with different characteristic impedances, and the expression for their reflection coefficient ⁇ is the same as that for ultrasound.
  • Z ⁇ sub> L ⁇ /sub> is the terminal load and Z ⁇ sub>0 ⁇ /sub> is the characteristic impedance.
  • These transmission and reflection characteristics can be expressed using S-parameters from microwave transmission line theory. Therefore, microwave transmission line theory can be used to facilitate the establishment of interface stiffness measurement models that reduce boundary effects.
  • the transmission and reflection propagation of ultrasonic waves is shown in Figure 2.
  • the top and bottom layers are piezoelectric wafers used to transmit and receive ultrasonic waves, while the remaining layers in the middle are metal bonding components.
  • Ultrasonic waves are reflected and transmitted not only at the contact interface, but also at the sensing boundary between the piezoelectric wafers and the metal layers, exhibiting both reflection and transmission characteristics.
  • the transmission coefficient B1 of the first transmitted wave can be expressed as:
  • the reflection coefficient C12 of the first reflected wave from the upper sensing boundary can be expressed as:
  • r ⁇ sub>i ⁇ /sub> is the reflection coefficient of the i-th interface
  • r ⁇ sub>inter ⁇ /sub> is the reflection coefficient of the contact interface
  • t ⁇ sub>i ′ ⁇ /sub> is the backpropagation transmission coefficient of the i-th interface.
  • the reflection coefficient C ⁇ sub>N ⁇ /sub>(N-1) of the first reflected wave from the lower sensing boundary can be expressed as:
  • the transmission coefficient of the i-th interface may be unequal in different propagation directions
  • the product of the transmission coefficients of the 1st and Nth interfaces is equal in different propagation directions due to the reversibility of the propagation process.
  • the geometric mean of the reflection coefficients is usually used as the composite reflection coefficient.
  • equation (7) can be simplified to
  • equation (7) can be further simplified to
  • the S11 and S22 parameters are often used to characterize reflection characteristics, while the S21 parameter is used to characterize transmission characteristics.
  • the TRDI measurement index eliminates the influence of sensing boundaries, retaining only the transmission coefficient of the contact interface. Therefore, utilizing the similarity between ultrasonic propagation theory and microwave transmission line theory helps to reduce boundary effects and improve the robustness of interface stiffness measurements.
  • the sensing boundary parameters exhibit a Gaussian distribution, with a maximum deviation rate of 36.4%.
  • Figure 3(b) shows the box plots of interface stiffness obtained by different methods. As can be seen from the figure, when the deviation rate of the coupling layer parameters is 36.4%, the interface stiffness deviation rate obtained by the traditional method is 61.9%. This indicates that fluctuations in the sensing boundary parameters amplify the measurement error of the traditional method. Therefore, for the traditional method, in order to reduce the impact of uncertainties in the sensing boundary parameters, multiple data acquisitions and statistical analyses should be performed in RIAP to ensure the accuracy of the measurement results.
  • the proposed method is less affected by uncertainties in sensing boundary parameters. This is because the proposed measurement index utilizes the intrinsic relationship between reflection and transmission information when calculating the transmission coefficient, thus reducing the impact of sensing boundary parameter uncertainties on the measurement results. Furthermore, in some practical measurement processes, RIAP is difficult to implement due to the special requirements of the measured object's spatial dimensions and operational processes. Therefore, compared with traditional methods, the proposed method achieves in-situ measurement of interface stiffness without the need for calibration reference data, making it more promising for practical applications.
  • this invention is based on the device base 1, and the entire device is constructed in the form of an upper and lower structure according to the requirements of ultrasonic transmission detection.
  • the device base 1 is connected to the upper turntable end cover 5 and the lower turntable end cover 7 via upper rolling bearing 9 and lower rolling bearing 10, respectively.
  • the upper linear guide rail 13, upper linear guide rail base 6, upper turntable end cover 5, hollow connecting cylinder 11, lower turntable end cover 7, lower linear guide rail base 8, and lower linear guide rail 18 are connected in sequence by bolts.
  • the upper servo motor 22, upper servo motor adapter plate 21, upper servo motor connecting plate 15, and upper linear slider are connected in sequence by bolts; the lower servo motor 30, lower servo motor connecting plate 20, and lower linear slider 19 are connected in sequence by bolts.
  • the upper servo motor 22 is connected to the upper servo motor turntable 23 via splines; the lower servo motor 30 is connected to the lower servo motor turntable 31 via splines.
  • the upper probe housing 27, upper probe connecting rod 26, upper probe connecting rod fixing block 25, upper servo motor rotating plate 24, and upper servo motor rotating disk 23 are connected in sequence by bolts;
  • the lower probe housing 35, lower probe connecting rod 34, lower probe connecting rod fixing block 33, lower servo motor rotating plate 32, and lower servo motor rotating disk 23 are connected in sequence by bolts.
  • the discs 31 are connected sequentially by bolts.
  • the upper ultrasonic probe 28 is fixed in the upper probe housing 27 under the action of the upper probe compression spring 29; the lower ultrasonic probe 36 is fixed in the lower probe housing 35 under the action of the lower probe compression spring 37.
  • the device base 1 and the hollow connecting cylinder 11 are hollow structures.
  • the electromagnet 12 and the adsorption cylinder 16 are attracted to each other to provide clamping displacement for the ultrasonic probe.
  • the upper probe compression spring 29 and the lower probe compression spring 37 provide clamping force for the ultrasonic probe.
  • Electromagnet 12 loses its magnetic force when de-energized, and separates from the adsorption cylinder 16 as the upper linear slider 14 and lower linear slider 19 separate.
  • the upper servo plate 24 and lower servo plate retract under the action of the upper servo 22 and lower servo 30, and the three evenly distributed positioning telescopic rods 3 are pressed into the main body 11 of the device and the hollow connecting cylinder 11, converting them into a retracted state. The entire device is removed from the internal structure of the aircraft engine.

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Abstract

本发明属于界面刚度检测技术领域，公开了一种借鉴微波传输线理论的航空发动机转子界面刚度原位超声检测方法与装置。该航空发动机转子界面刚度原位超声检测装置以装置基体为基础，以中间连接结构形成上下结构的分布形式，两个探头分别以舵机转盘为基准实现展开、收缩运动。该检测装置通过夹持机构进行定位与固定，通过电磁铁和吸附圆柱提供探头的夹紧位移，通过压簧提供探头的夹紧力。本发明的航空发动机转子界面刚度原位超声检测装置能够借鉴微波传输线理论消减传感边界的随机性影响，能够在航空发动机狭小空间开展界面刚度检测；利用弹簧提供压力实现较好的重复性；利用连接筒实现上下结构的同步转动提高了上下探头的同轴度。

Description

一种借鉴微波传输线理论的航空发动机转子界面刚度原位超声检测方法与装置 技术领域
本发明属于界面刚度检测技术领域，涉及一种借鉴微波传输线理论的航空发动机转子界面刚度原位超声检测方法与装置。
背景技术
航空发动机各组件之间通过螺栓进行连接，受加工、装配等因素的限制，使得发动机转子系统中存在许多连接结构，其局部接触状态改变会使转子系统产生附加不平衡量，引起整机振动问题。因此，对航空发动机内腔部位界面刚度检测具有重要意义。
与其他测量手段相比，超声测量技术具有不受材料属性限制、原位测量能力强、界面测量敏感度高的优势，满足航发转子原位测量的基本条件。其中尤为重要的是，界面刚度测量方法的鲁棒性与航发转子狭小空间的操作性。
目前现有的界面刚度检测存在以下问题：
1)无法原位检测，李瑞的一种便携式环刚度检测装置及作业方法需要将待测管道放置于检测平台上进行检测。对于航发转子，由于检测工艺要求，需要在特定工位进行检测，增加了航发转子界面刚度检测的难度。
2)可达性差，姜春玉的一种基于超声检测的复合材料及其相关构件无损检测装置采用开放式检测装置。对于航发转子，压气机鼓筒盘位置内部空间结构狭小，操作空间有限，现有开放式检测设备难以进入，现有的转子难以进行相关的界面刚度检测工作。
3)鲁棒性差，穆晓凯的一种基于固体耦合的界面刚度检测装置并未考虑传感边界参数的不确定性。对于航发转子，在检测过程中传感边界参数具有不确定性，极易导致测量性能下降，限制了界面刚度测量的应用。
发明内容
本发明的目的是解决航空发动机界面刚度检测难的问题，提供一种借鉴微波传输线理论的航空发动机转子界面刚度原位超声检测方法与装置。本发明能够借鉴微波传输线理论消减传感边界的随机性影响，能够在航空发动机狭小空间开展界面刚度检测，能够利用弹簧提供压力实现较好的重复性，利用连接筒实现上下结构的同步转动提高了上下探头的同轴度。
本发明的技术方案：
一种借鉴微波传输线理论的航空发动机转子界面刚度原位超声检测方法，利用航空发动机转子界面刚度原位超声检测装置，将固定卡爪2夹持在航空发动机内环面上；展开上超声探头28、下超声探头36使其分别位于待测点上方和下方；通过电磁铁12与吸附圆柱16的相互吸附作用使上超声探头28与下超声探头36压紧于待检测位置；通过上超声探头28与下超声探头36发射超声信号，获取透射系数B1、上表面反射系数C12、下表面反射系数C43，再通过计算得到待测点界面刚度；
待测点界面刚度TRDI表达式为：
在微波传输线测量中，S11参数和S22参数常用于表征反射特性，S21参数用于表征透射特性，由此可以获得Cij和B1，同时TRDI测量指标消除了传感边界的影响，只保留了接触界面的透射系数。因此，利用超声波传播理论与微波传输线理论的相似性，有利于消减边界效应，提高界面刚度测量的鲁棒性。
一种借鉴微波传输线理论的航空发动机转子界面刚度原位超声检测装置，包括装置基体1、固定卡爪2、定位伸缩杆3、固定压簧4、上转盘端盖5、上直线导轨底座6、下转盘端盖7、下直线导轨底座8、上滚动轴承9、下滚动轴承 10、中空连接筒11、电磁铁12、上直线导轨13、上直线滑块14、上舵机连接板15、吸附圆柱16、吸附圆柱座17、下直线导轨18、下直线滑块19、下舵机连接板20、上舵机转接板21、上舵机22、上舵机转盘23、上舵机转板24、上探头连杆固定块25、上探头连杆26、上探头外壳27、上超声探头28、上探头压簧29、下舵机30、下舵机转盘31、下舵机转板32、下探头连杆固定块33、下探头连杆34、下探头外壳35、下超声探头36和下探头压簧37；
装置基体1与中空连接筒11同心，均为中空圆柱结构，三个定位伸缩杆3均布在装置基体1与中空连接筒11内，位于中空连接筒11外的定位伸缩杆3上套装有固定压簧4，定位伸缩杆3在固定压簧4的作用下进行航空发动机内圆环面的定位与固定；装置基体1的上下端分别通过上滚动轴承9、下滚动轴承10与上转盘端盖5、下转盘端盖7相连，上转盘端盖5与下转盘端盖7通过中空连接筒11相连实现同步转动，并夹持住装置基体1；上转盘端盖5与上直线导轨底座6连接，上直线导轨底座6与上直线导轨13连接，下转盘端盖7与下直线导轨底座8连接，下直线导轨底座8与下直线导轨18连接；电磁铁12与上舵机连接板15连接，吸附圆柱16与吸附圆柱座17相连，吸附圆柱座17与下舵机连接板20连接；电磁铁12与吸附圆柱16的相互吸附为超声探头提供夹紧位移；上舵机22通过上舵机转接板21与上舵机连接板15连接，上舵机转板24通过上舵机转盘23与上舵机22连接，上探头连杆26通过上探头连杆固定块25与上探头转接板54连接，上超声探头28通过上探头外壳27和上探头压簧29与上探头连杆26连接；下舵机30与下舵机连接板20连接，下舵机转板32通过下舵机转盘31与下舵机30连接，下探头连杆34通过下探头连杆固定块33与下探头转接板63连接，下超声探头36通过下探头压簧37和下探头外壳35与下探头连杆34连接；上直线滑块14与上舵机连接板15固定连接，上直线滑 块14在上直线导轨13上的移动带动上舵机22与上超声探头28的直线运动，下直线滑块19与下舵机连接板20固定连接，下直线滑块19在下直线导轨18上的移动带动下舵机30与下超声探头36的直线运动；上舵机22通过花键与上舵机转盘23连接，上舵机22输出轴的转动带动上舵机转板24与上超声探头28的转动，下舵机30通过花键与下舵机转盘31连接，下舵机30输出轴的转动带动下舵机转板32与下超声探头36的转动；上超声探头28与下超声探头36分别受上探头压簧29与下探头压簧37作用压靠在上探头外壳27与下探头外壳35中；
电磁铁12与吸附圆柱16的相互吸附为上超声探头28与下超声探头36提供夹紧位移；上超声探头28与下超声探头36在电磁铁12与吸附圆柱16产生的夹紧位移作用下受上探头压簧29与下探头压簧37作用产生夹紧力；
在非检测阶段，电磁铁12没有通电不具有磁性，上舵机连接板15与下舵机连接板20彼此分离，上超声探头28与下超声探头36处于收起状态，此时上超声探头28与下超声探头36不具有夹紧力；在检测阶段，上超声探头28与下超声探头36展开到待测位置，电磁铁12通电产生磁性，与吸附圆柱16相互吸附，上舵机连接板15与下舵机连接板20相互靠近，上超声探头28与下超声探头36也随之相应靠近，在上探头压簧29与下探头压簧37作用下产生夹紧力，开展界面刚度检测工作；
上舵机转板24与下舵机转板32在初始阶段处于收起状态，在固定卡爪2在定位伸缩杆3与固定压簧4作用下完成定位与固定后展开上舵机转板24与下舵机转板32，使超声探头移动到待检测区域。
定位伸缩杆3上具有凸台结构，在收缩状态时可卡在装置基体1的内平面上，防止在固定压簧4的作用下弹出，在展开状态时与装置基体1的凹槽相配 合，使固定卡爪2以特定姿态弹出，固定在发动机内圆环面上。
本发明的有益效果：本发明的特点在于能够在航空发动机狭小空间开展界面刚度检测，能够利用弹簧杆提供压力实现较好的重复性，利用上下结构同步转动实现较好的稳定性。
附图说明
图1为超声波和微波传输的相似性示意图：(a)微波传输的阻抗不匹配；(b)超声传播的界面阻抗不连续；
图2为多层接触界面下超声波的透射和反射结果图；
图3为所提出方法与传统方法的鲁棒性对比结果：(a)边界参数的统计直方图；(b)不同方法获得的界面刚度盒状图；
图4为检测装置总体结构示意图；
图5为检测装置侧视图，为示出检测装置总体收起时状态；
图6为示出检测装置内部连接结构示意图。
图中：1装置基体；2固定卡爪；3定位伸缩杆；4固定压簧；5上转盘端盖；6上直线导轨底座；7下转盘端盖；8下直线导轨底座；9上滚动轴承；10下滚动轴承；11中空连接筒；12电磁铁；13上直线导轨；14上直线滑块；15上舵机连接板；16吸附圆柱；17吸附圆柱座；18下直线导轨；19下直线滑块；20下舵机连接板；21上舵机转接板；22上舵机；23上舵机转盘；24上舵机转板；25上探头连杆固定块；26上探头连杆；27上探头外壳；28上超声探头；29上探头压簧；30下舵机；31下舵机转盘；32下舵机转板；33下探头连杆固定块；34下探头连杆；35下探头外壳；36下超声探头；37下探头压簧。
具体实施方式
以下结合附图和技术方案，进一步说明本发明的具体实施方式。
界面刚度检测方法：
当固体中的超声波以较高频率传播时，超声波传播理论和微波传输线理论在控制方程、边界条件和反射定律上具有较强的相似性。微波的麦克斯韦方程由四个方程和四个变量(电场强度、磁场强度、电荷密度和电流密度)组成。类似地，固体中的超声波也是由四个方程和四个变量(应变、应力、位移和速度)组成。此外，如图1所示，微波传输线和固体中的超声波在非连续界面处也具有相似的传播规律。超声波的反射系数R取决于两种材料的声阻抗：
其中，Z1和Z2表示界面两侧的声阻抗。
微波在具有不同特性阻抗的传输线中传播时也具有反射特性，其反射系数Γ的表达式形式与超声波相同。
其中ZL是终端负载，Z0是特征阻抗。而这种透射和反射特性可以用微波传输线理论中的S参数表达。因此，可以借鉴微波传输线理论，促进建立消减边界效应的界面刚度测量模型。
超声波的透射和反射传播如图2。如图所示，顶层和底层是压电晶片，用于发射和接收超声波，中间的其余各层是金属被连接件。超声波不仅在接触界面处反射和透射，而且在压电晶片和金属层之间的传感边界处也存在反射特性和透射特性。
如图2所示，每次当超声波穿过界面时，透射波能量就会损失一部分。第一个透射波的透射系数B1可以表示为：
其中，ti是第i层界面的透射系数，γ是传播常数，Di为第i层结构的厚度。此外，上方传感边界的第一反射波的反射系数C12可以表示为：
其中ri是第i层界面的反射系数，rinter是接触界面的反射系数，ti′是第i层界面的反向传播透射系数。
同样，下方传感边界的第一个反射波的反射系数CN(N-1)可以表示为：
尽管第i层界面的透射系数在不同传播方向存在不相等的可能性，但由于传播过程具有可逆性，第1层界面和第N层界面在不同的传播方向上透射系数的乘积是相等的。
t1×tN＝t1′×tN′      
(6)
由于在有限厚度的金属固体介质中声学传播损耗相对较小，所以能量损耗主要来自于非连续界面，忽略了连续固体介质中的能量传播损耗。同时假设各接触界面的能量传输特性相同，通过联立式(3)、(4)、(5)和(6)，可以得到
其中，通常将反射系数的几何平均值作为综合反射系数。
对于双层连接结构(N＝3)，即双层连接结构中含有一个接触界面和两个传感边界，式(7)可以简化为
考虑到传感边界参数存在随机误差和探头位姿不确定性的影响，单个超声测量指标的鲁棒性较差，所以提出了一种综合透射信息和反射信息的界面刚度测量指标(TRDI)。由式(9)，可以获得与双层连接结构相对应的界面刚度测量指标TRDI表达式。
同理，对于三层连接结构(N＝4)，即三层连接结构中含有两个接触界面和两个传感边界，式(7)可以进一步被简化为
同样的，由式(11)，可以获得与三层连接结构相对应的界面刚度测量指标TRDI表达式。
此外，在微波传输线测量中，S11参数和S22参数常用于表征反射特性，S21参数用于表征透射特性，由此可以获得Cij和B1，同时TRDI测量指标消除了传感边界的影响，只保留了接触界面的透射系数。因此，利用超声波传播理论与微波传输线理论的相似性，有利于消减边界效应，提高界面刚度测量的鲁棒性。
如图3(a)所示，传感边界参数呈现高斯分布的特点，其最大偏差率为36.4％。 图3(b)显示了不同方法获得的界面刚度盒状图。由图可以看出，当耦合层参数的偏差率为36.4％时，传统方法得到的界面刚度偏差率为61.9％。这表明传感边界参数的波动会放大传统方法的测量误差。因此，对于传统方法而言，为了减少传感边界参数的不确定性带来的影响，应在RIAP中进行多次采集和统计分析，以确保测量结果的准确性。
从结果也可以看出，与传统方法相比，所提出方法受传感边界参数不确定性的影响较小。其原因在于，所提出的测量指标在计算透射系数时利用了反射信息和透射信息之间的内在关系，消减了传感边界参数不确定性对测量结果的影响。此外，在某些实际测量过程中，由于测量对象的空间尺寸、操作工艺等特殊性要求，RIAP难以实施。因此，与传统方法相比，所提出的方法实现了无需标定基准数据的界面刚度原位测量，使其更具有实际应用前景。
借鉴微波传输线理论对航空发动机转子界面刚度原位超声检测装置进行设计。
如图4至图6所示，本发明以装置基体1为基础，根据超声透射检测的要求，整个装置以上下结构的形式构成。装置基体1分别与上转盘端盖上转盘端盖5、下转盘端盖7通过上滚动轴承9、下滚动轴承10连接。上直线导轨13、上直线导轨底座6、上转盘端盖5、中空连接筒11、下转盘端盖7、下直线导轨底座8，下直线导轨18依次通过螺栓进行连接。上舵机22、上舵机转接板21、上舵机连接板15、上直线滑块依次通过螺栓连接；下舵机30、下舵机连接板20、下直线滑块19依次通过螺栓连接。上舵机22与上舵机转盘23通过花键连接；下舵机30与下舵机转盘31通过花键连接。上探头外壳27、上探头连杆26、上探头连杆固定块25、上舵机转板24、上舵机转盘23依次通过螺栓连接；下探头外壳35、下探头连杆34、下探头连杆固定块33、下舵机转板32、下舵机转 盘31依次通过螺栓连接。上超声探头28在上探头压簧29作用下固定在上探头外壳27中；下超声探头36在下探头压簧37作用下固定在下探头外壳35中。
装置基体1与中空连接筒11为中空结构，电磁铁12与吸附圆柱16相互吸附为超声探头提供夹紧位移，上探头压簧29与下探头压簧37为超声探头提供夹紧力。
本发明的实施步骤为：
1)初始阶段：三个均布的定位伸缩杆3在凸台与固定压簧4限制下收缩于装置基体1与中空连接筒11内，上舵机转板24处于竖直收起状态，下舵机转板64处于侧边收起状态。此时整个装置处于收缩状态，通过航空发动机狭小入口进入转子内腔中。
2)检测准备阶段：到达指定位置后，转动三根定位伸缩杆3使其上凸台与装置基体1的凹槽重合，并在固定压簧4作用下弹出，其末端的固定卡爪2夹持在航空发动机内环面上，并在相同弹簧力作用下保证了装置基体1与航空发动机内圆环面的同心定位效果。在定位伸缩杆3、固定卡爪2完成定位夹紧功能之后进行上舵机转板24与下舵机转板32的展开，使上超声探头28与下超声探头36分别处于待测区域的上方与下方。
3)检测进行阶段：由于定位伸缩杆3的伸出，装置基体1与中空连接筒11的中心位置处于中空状态，在电磁铁12与吸附圆柱16的相互吸附作用下上舵机连接板15与下舵机连接板20相互靠近并连接为一个整体。上超声探头28、下超声探头36间与航空发动机被测结构形成10N的夹紧力，保证上下界面接触与受力状态相同。完成一个局部位置的界面刚度检测之后，电磁铁12断电失去磁力，将上转盘端盖5转动特定角度，到达下一个待测局部位置，重复上述步骤完成整周的测量。
4)检测结束阶段：电磁铁12断电失去磁力，与吸附圆柱16分别随上直线滑块14与下直线滑块19的分离而分离。上舵机转板24与下舵机转板在上舵机22与下舵机30作用下收起，三个均布的定位伸缩杆3压入装置主体11与中空连接筒11转换为收缩状态，整个装置移出航空发动机内腔结构。

Claims (3)

  1. 一种借鉴微波传输线理论的航空发动机转子界面刚度原位超声检测装置，其特征在于，该航空发动机转子界面刚度原位超声检测装置包括装置基体(1)、固定卡爪(2)、定位伸缩杆(3)、固定压簧(4)、上转盘端盖(5)、上直线导轨底座(6)、下转盘端盖(7)、下直线导轨底座(8)、上滚动轴承(9)、下滚动轴承(10)、中空连接筒(11)、电磁铁(12)、上直线导轨(13)、上直线滑块(14)、上舵机连接板(15)、吸附圆柱(16)、吸附圆柱座(17)、下直线导轨(18)、下直线滑块(19)、下舵机连接板(20)、上舵机转接板(21)、上舵机(22)、上舵机转盘(23)、上舵机转板(24)、上探头连杆固定块(25)、上探头连杆(26)、上探头外壳(27)、上超声探头(28)、上探头压簧(29)、下舵机(30)、下舵机转盘(31)、下舵机转板(32)、下探头连杆固定块(33)、下探头连杆(34)、下探头外壳(35)、下超声探头(36)和下探头压簧(37)；
    装置基体(1)与中空连接筒(11)同心，均为中空圆柱结构，三个定位伸缩杆(3)均布在装置基体(1)与中空连接筒(11)内，位于中空连接筒(11)外的定位伸缩杆(3)上套装有固定压簧(4)，定位伸缩杆(3)在固定压簧(4)的作用下进行航空发动机内圆环面的定位与固定；装置基体(1)的上下端分别通过上滚动轴承(9)、下滚动轴承(10)与上转盘端盖(5)、下转盘端盖(7)相连，上转盘端盖(5)与下转盘端盖(7)通过中空连接筒(11)相连实现同步转动，并夹持住装置基体(1)；上转盘端盖(5)与上直线导轨底座(6)连接，上直线导轨底座(6)与上直线导轨(13)连接，下转盘端盖(7)与下直线导轨底座(8)连接，下直线导轨底座(8)与下直线导轨(18)连接；电磁铁(12)与上舵机连接板(15)连接，吸附圆柱(16)与吸附圆柱座(17)相连，吸附圆柱座(17)与下舵机连接板(20)连接；电磁铁(12)与吸附圆柱(16)的相互吸附为超声探头提供夹紧位移；上舵机(22)通过上舵机转接板 (21)与上舵机连接板(15)连接，上舵机转板(24)通过上舵机转盘(23)与上舵机(22)连接，上探头连杆(26)通过上探头连杆固定块(25)与上探头转接板54连接，上超声探头(28)通过上探头外壳(27)和上探头压簧(29)与上探头连杆(26)连接；下舵机(30)与下舵机连接板(20)连接，下舵机转板(32)通过下舵机转盘(31)与下舵机(30)连接，下探头连杆(34)通过下探头连杆固定块(33)与下探头转接板63连接，下超声探头(36)通过下探头压簧(37)和下探头外壳(35)与下探头连杆(34)连接；上直线滑块(14)与上舵机连接板(15)固定连接，上直线滑块(14)在上直线导轨(13)上的移动带动上舵机(22)与上超声探头(28)的直线运动，下直线滑块(19)与下舵机连接板(20)固定连接，下直线滑块(19)在下直线导轨(18)上的移动带动下舵机(30)与下超声探头(36)的直线运动；上舵机(22)通过花键与上舵机转盘(23)连接，上舵机(22)输出轴的转动带动上舵机转板(24)与上超声探头(28)的转动，下舵机(30)通过花键与下舵机转盘(31)连接，下舵机(30)输出轴的转动带动下舵机转板(32)与下超声探头(36)的转动；上超声探头(28)与下超声探头(36)分别受上探头压簧(29)与下探头压簧(37)作用压靠在上探头外壳(27)与下探头外壳(35)中；
    电磁铁(12)与吸附圆柱(16)的相互吸附为上超声探头(28)与下超声探头(36)提供夹紧位移；上超声探头(28)与下超声探头(36)在电磁铁(12)与吸附圆柱(16)产生的夹紧位移作用下受上探头压簧(29)与下探头压簧(37)作用产生夹紧力；
    在非检测阶段，电磁铁(12)没有通电不具有磁性，上舵机连接板(15)与下舵机连接板(20)彼此分离，上超声探头(28)与下超声探头(36)处于收起状态，此时上超声探头(28)与下超声探头(36)不具有夹紧力；在检测 阶段，上超声探头(28)与下超声探头(36)展开到待测位置，电磁铁(12)通电产生磁性，与吸附圆柱(16)相互吸附，上舵机连接板(15)与下舵机连接板(20)相互靠近，上超声探头(28)与下超声探头(36)也随之相应靠近，在上探头压簧(29)与下探头压簧(37)作用下产生夹紧力，开展界面刚度检测工作；
    上舵机转板(24)与下舵机转板(32)在初始阶段处于收起状态，在固定卡爪(2)在定位伸缩杆(3)与固定压簧(4)作用下完成定位与固定后展开上舵机转板(24)与下舵机转板(32)，使超声探头移动到待检测区域。
  2. 根据权利要求1所述的航空发动机转子界面刚度原位超声检测装置，其特征在于，定位伸缩杆(3)上具有凸台结构，在收缩状态时卡在装置基体(1)的内平面上，防止在固定压簧(4)的作用下弹出，在展开状态时与装置基体(1)的凹槽相配合，使固定卡爪(2)以特定姿态弹出，固定在发动机内圆环面上。
  3. 一种借鉴微波传输线理论的航空发动机转子界面刚度原位超声检测方法，其特征在于，
    利用航空发动机转子界面刚度原位超声检测装置，将固定卡爪(2)夹持在航空发动机内环面上；展开上超声探头(28)、下超声探头(36)使其分别位于待测点上方和下方；通过电磁铁(12)与吸附圆柱(16)的相互吸附作用使上超声探头(28)与下超声探头(36)压紧于待检测位置；通过上超声探头(28)与下超声探头(36)发射超声信号，获取透射系数B1、上表面反射系数C12、下表面反射系数C43，再通过计算得到待测点界面刚度；
    待测点界面刚度TRDI表达式为：
PCT/CN2024/107162 2024-07-24 2024-07-24 一种借鉴微波传输线理论的航空发动机转子界面刚度原位超声检测方法与装置 Pending WO2026020342A1 (zh)

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