Spraying pipe surface acoustic load structure response testing device and testing method

Abstract

The invention provides a spray pipe surface acoustic load structure response testing device and method, and belongs to the technical field of engine spray pipes, the device comprises a spray pipe shrinkage ratio test piece, the spray pipe shrinkage ratio test piece is provided with a spray pipe outer wall and a spray pipe inner wall, and an outer duct is formed between the spray pipe outer wall and the spray pipe inner wall; a thin-wall structure is arranged on the outer surface of the rear side of an airflow flow path of the outer wall of the spray pipe, and a hollow structure is formed between the thin-wall structure and the outer wall of the spray pipe; the test bracket is mounted on a table board of a test site and at least partially covers the thin-wall structure on the outer wall of the spray pipe; and the acoustic sensor is mounted on the test bracket and is used for obtaining acoustic load distribution and acoustic vibration response characteristics of the spray pipe shrinkage ratio test piece. The testing device can ensure that the thin-wall structure can obtain the structural response characteristic consistent with the outer wall of the spray pipe under the action of equivalent external force, flow interference in the spray pipe is greatly reduced, and small-load-field high-signal-to-noise-ratio testing of the outer wall of the spray pipe is achieved.

Description

Technical Field

[0001] The present application belongs to the field of aero-engine technology, and in particular relates to a nozzle surface acoustic load structural response testing device and testing method. Background Art

[0002] The surface of aircraft engine nozzle components has random broadband vibrations generated by high-intensity aerodynamic noise. At certain frequencies, it may excite structural vibrations on the nozzle surface, thereby generating high-frequency stress and inducing high-cycle fatigue failure on the outer wall of the nozzle. Therefore, the acoustic fatigue of the thin-walled structure of the nozzle refers to the structural fatigue damage phenomenon caused by the nozzle surface under the excitation of acoustic loads. The effect of noise on the outer wall of the nozzle is essentially a dynamic random pressure load with spatial distribution and certain frequency distribution characteristics. Since the jet noise spectrum is a broadband noise spectrum, the outer wall components of the nozzle are extremely prone to high-cycle fatigue under noise excitation environment.

[0003] Since it is difficult to test the acoustic load and acoustic vibration response on the surface of a real engine nozzle, noise testing is usually carried out on a scaled test piece. The acoustic load of the scaled test piece nozzle is small, and the outer wall load is easily affected by the fluid disturbance in the nozzle, such as Figure 1 The figure shows a schematic diagram of a traditional test method for obtaining the load distribution on the nozzle surface using a pulsating pressure sensor. Since the installation process of the pulsating pressure sensor 1 in the traditional test method causes damage to the nozzle outer wall 2, which changes the structural rigidity of the nozzle outer wall 2, it is impossible to establish an equivalent study on the acoustic vibration response of the nozzle outer wall based on a scaled model. In addition, since the acoustic load on the nozzle outer wall after scaling is small, the test error using the pulsating pressure sensor 1 is large.

[0004] Based on the above reasons, a non-contact nozzle outer wall acoustic load response test method that can reduce the influence of internal flow is needed to obtain the acoustic load distribution and acoustic vibration response characteristics of the scaled nozzle surface, providing technical support for nozzle structure design and acoustic fatigue control. Summary of the Invention

[0005] The purpose of the present application is to provide a nozzle surface acoustic load structural response testing device and testing method to solve or alleviate at least one problem in the background technology.

[0006] On the one hand, the technical solution of the present application is: a nozzle surface acoustic load structural response test device, comprising:

[0007] A scaled-down nozzle test piece, comprising a nozzle outer wall and a nozzle inner wall, wherein an outer duct is formed between the nozzle outer wall and the nozzle inner wall, and a thin-walled structure is provided on an outer surface of the nozzle outer wall on a rear side of an airflow path, and a hollow structure is formed between the thin-walled structure and the nozzle outer wall;

[0008] A test bracket, which is mounted on a test site table and at least partially covers the thin-walled structure on the outer wall of the nozzle;

[0009] The acoustic sensor is installed on the test bracket and is used to obtain the acoustic load distribution and acoustic vibration response characteristics of the nozzle scale test piece.

[0010] In at least one embodiment of the present application, the axial length of the thin-wall structure at least partially covers the outer surface of the nozzle outer wall corresponding to the end position of the nozzle inner wall.

[0011] In at least one embodiment of the present application, the material of the thin-wall structure is the same as the material of the outer wall of the nozzle.

[0012] In at least one embodiment of the present application, the thickness of the thin-walled structure is 0.3 mm to 0.5 mm.

[0013] In at least one embodiment of the present application, the test bracket includes a cover, a cover bracket, an adjustable height support rod and a mounting base, the mounting base is fixed to the test site platform through a connecting piece, the adjustable height support rod is installed on the mounting base, the cover is fixed to the adjustable height support rod through the cover bracket, the acoustic sensor is installed on the cover, and the height of the cover is adjusted by the adjustable height support rod so that the relative gap between the acoustic sensor and the nozzle outer wall and / or thin-wall structure of the nozzle scale test piece is uniform.

[0014] In at least one embodiment of the present application, the cover shell has hollow holes in the circumferential direction and / or the axial direction, so that the cover shell has low reflection and high transmission characteristics.

[0015] In at least one embodiment of the present application, the surface of the cover is subjected to sound absorption treatment.

[0016] In at least one embodiment of the present application, the acoustic sensor is mounted on the cover of the test stand via a threaded structure, and the threaded structure enables the distance between the acoustic sensor and the cover to be adjustable.

[0017] In at least one embodiment of the present application, the distance between the acoustic microphone and the outer wall of the nozzle and / or the thin-wall structure is 0.5 mm to 1 mm.

[0018] On the other hand, the technical solution provided by the present application is: a method for performing a nozzle surface acoustic load structural response test using any of the nozzle surface acoustic load structural response test devices described above, the method comprising:

[0019] S10, assembling the test stand, fastening the mounting base of the test stand to the table surface of the test site through a connector, and sequentially installing an adjustable height support rod, a cover bracket, and a cover on the mounting base;

[0020] S20, inserting the nozzle scale test piece into a cover of a test stand so that the axis of the nozzle scale test piece coincides with the axis of the cover of the test stand;

[0021] S30, mounting the acoustic sensors on the housing, adjusting the height of the acoustic sensors using an adjustable height support rod, and adjusting the relative position between the acoustic sensors and the housing so that the distance between each acoustic sensor and the nozzle outer wall or thin-wall structure is the same and is a predetermined value;

[0022] S40, arranging strain gauges on the surface of the nozzle outer wall to form dynamic stress measuring points, wherein the distribution of the dynamic stress measuring points covers the surface of the nozzle outer wall;

[0023] S50, a tapping method is used to perform modal tapping on the outer wall surface of the nozzle, and a unified dynamic test platform is used to test and analyze the acoustic load and dynamic stress measurement points of the nozzle scale test piece. The cross-spectrum analysis technology is used to perform correlation analysis on the acoustic load peak frequency band and dynamic stress response frequency band of the nozzle scale test piece, thereby obtaining the acoustic load distribution and acoustic vibration response characteristics of the nozzle scale test piece. Finally, the acoustic vibration response characteristics of the real nozzle are obtained through the acoustic vibration response characteristics of the nozzle scale test piece.

[0024] The test device of the present application can ensure that the thin-walled structure can obtain structural response characteristics consistent with the outer wall of the nozzle under the action of equivalent external forces, greatly reduce the flow interference inside the nozzle, and realize the high signal-to-noise ratio test of the small load field of the outer wall of the nozzle. The test method of the present application reduces the interference of the airflow and equipment vibration inside the nozzle on the acoustic load test of the outer wall of the jet by using a thin-walled structure with equivalent acoustic load and acoustic vibration response of the outer wall of the nozzle based on a nozzle scale test piece with similar structure, realizes the acoustic load test of the outer wall of the nozzle through a non-contact pressure field test method, optimizes the layout scheme of the dynamic stress test of the outer wall of the nozzle by combining simulation and tapping, and finally obtains the acoustic load distribution and acoustic vibration response characteristics of the nozzle surface through a unified dynamic test platform, solves the problem of nozzle acoustic vibration response test and analysis, and provides method support for nozzle structure design and acoustic fatigue suppression. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solutions provided by this application, the following is a brief introduction to the accompanying drawings. Obviously, the accompanying drawings described below are only some embodiments of this application.

[0026] Figure 1 Schematic diagram of the traditional method for testing nozzle surface acoustic loads using a pulsating pressure sensor.

[0027] Figure 2 This is a schematic diagram of the nozzle scale test piece of this application.

[0028] Figure 3 Schematic diagram of the test bracket for this application. DETAILED DESCRIPTION

[0029] In order to make the purpose, technical solutions and advantages of the implementation of this application clearer, the technical solutions in the embodiments of this application will be described in more detail below in conjunction with the drawings in the embodiments of this application.

[0030] In order to reduce the influence of the internal flow of the nozzle on the acoustic load test of the nozzle outer wall, and reduce the influence of the pulsating pressure sensor on the structural strength of the nozzle, the present application provides a nozzle surface acoustic load structural response test device and test method, which solves the problems of the lack of existing nozzle outer wall structural acoustic load test capability and low test accuracy.

[0031] like Figure 2 and Figure 3 As shown, first, the present application provides a nozzle surface acoustic load structural response test device, the device 100 includes a nozzle scale test piece 10, a test bracket 20 and an acoustic sensor 30.

[0032] The nozzle scale test piece 10 is designed to reduce internal nozzle flow disturbances, based on the requirements of engine nozzle noise research. The scale test piece 10 typically includes a nozzle outer wall 11, a nozzle inner wall 12, and a cone 13, arranged in sequence from the outside inward. An outer duct 15 is formed between the nozzle outer wall 11 and the nozzle inner wall 12, and an inner duct 16 is formed between the nozzle inner wall 12 and the cone 13. In some embodiments of the present application, the nozzle outer wall 11, the nozzle inner wall 12, and the cone 13 are typically made of high-temperature resistant metal materials, such as titanium alloys or high-temperature alloys. They can also be made of composite materials, such as ceramic-based composite materials.

[0033] A thin-walled structure 14 is provided on the outer surface of the rear side of the airflow path of the nozzle outer wall 11. The thin-walled structure 14 is circumferentially wrapped around the nozzle outer wall 11, and a certain gap is formed between the thin-walled structure 14 and the nozzle outer wall 11, thereby forming a hollow structure between the thin-walled structure 14 and the nozzle outer wall 11. In some embodiments of the present application, the thin-walled structure 14 can be fixed to the nozzle outer wall 11 by welding, or it can be fixed to the nozzle outer wall 11 by riveting. Furthermore, the edge of the hollow structure is a sealing structure. In order to improve the sealing performance of the hollow structure, a sealing layer can be provided between the thin-walled structure 14 and the nozzle outer wall 11. Exemplarily, the sealing layer can be a high-temperature resistant sealing coating coated on the thin-walled structure 14 or the nozzle outer wall 11, such as a phosphate-based coating or a nano-ceramic coating, or it can also be a high-temperature resistant sealing gasket provided on the thin-walled structure 14 or the nozzle outer wall 11, such as a metal sealing gasket or a ceramic fiber sealing gasket.

[0034] The thin-walled structure 14 has a certain length in the axial direction of the nozzle and is located at a position on the nozzle outer wall 11 where the vibration response is most intense. Typically, the thin-walled structure 14 is located on the nozzle outer wall 14 at the end of the nozzle inner wall 12, and at least partially covers the end of the nozzle inner wall 12 in the axial direction. The airflow flowing through the duct 15 typically generates a relatively intense acoustic load on the nozzle outer wall 11 at the end of the nozzle inner wall 12, causing the nozzle outer wall 11 to produce a structural vibration response.

[0035] The thin-walled structure 14 is made of a material consistent with the nozzle outer wall 11. For example, if the nozzle outer wall 11 is made of a high-temperature resistant metal, the thin-walled structure 11 should also be made of a high-temperature resistant metal. Furthermore, the thickness of the thin-walled structure 14 is typically set to 0.3 mm to 0.5 mm. This thin structure ensures that the vibration response of the nozzle outer wall 11 under acoustic loads is clearly transmitted to the thin-walled structure 14, and the thin-walled structure 14 achieves structural response characteristics consistent with those of the nozzle outer wall 11.

[0036] This application utilizes numerical and analytical methods to determine the thin-walled structure 14 disposed on the nozzle outer wall 11, ensuring that the thin-walled structure 14 achieves structural response characteristics consistent with those of the nozzle outer wall 11 under equivalent external forces. This significantly reduces internal flow disturbances within the nozzle and enables high signal-to-noise ratio testing of the nozzle outer wall in a small load field. This application overcomes the interference that vibrations of nozzle scaled components and internal flow disturbances can cause during acoustic load and dynamic stress testing of the nozzle outer wall in prior art, enabling quantitative testing of the acoustic vibration response of the nozzle outer wall.

[0037] Acoustic sensors 30 are arranged circumferentially and / or axially outside the thin-walled structure 14 on the nozzle outer wall 11 to measure the acoustic loads borne by the thin-walled structure 14. For example, in this embodiment of the present application, four rows of acoustic sensors 30 are arranged axially, and five acoustic sensors 30 are evenly distributed circumferentially. As a result, acoustic sensors 30 are arranged both circumferentially and axially outside the thin-walled structure 14 of the nozzle scale test piece 10, ensuring that the test positions of the acoustic sensors 30 cover the structural surface of the nozzle outer wall 11. It is understood that depending on the axial length of the thin-walled structure 14, only one row of acoustic sensors 30 may be arranged on the thin-walled structure 14. However, typically, multiple acoustic sensors 30 are arranged circumferentially to achieve full measurement of the circumference of the thin-walled structure 14.

[0038] Since the structure of the nozzle scaled-down test piece 10 is scaled down compared to the real nozzle, the acoustic load borne by the nozzle scaled-down test piece 10 is also scaled down. Therefore, the acoustic load borne by the nozzle outer wall 11 of the nozzle scaled-down test piece 10 is relatively small. The traditional pulsating pressure sensor has low test accuracy and will destroy the structural characteristics of the nozzle outer wall. Therefore, the present application adopts a pressure field acoustic sensor to perform acoustic load testing on the nozzle outer wall 11, wherein the size of the pressure field acoustic sensor can be determined according to the jet noise simulation calculation spectrum to ensure that the pressure field acoustic sensor can accurately identify the acoustic load of the jet noise.

[0039] In the present application, the distance d between the pressure field acoustic microphone and the thin-wall structure 14 satisfies the following formula (1) to ensure that the direct noise and reflected noise received by the pressure field acoustic sensor have the same amplitude, so that the noise load at the pressure field acoustic sensor can truly reflect the acoustic load characteristics of the nozzle outer wall 14, thereby realizing non-contact high-precision nozzle outer wall load testing.

[0040]

[0041] Wherein, d is the distance between the pressure field acoustic microphone and the thin-walled structure 14;

[0042] h is the perpendicularity between the pressure field acoustic microphone and the thin-walled structure 14;

[0043] R is the reflection coefficient.

[0044] In some embodiments of the present application, the distance d between the pressure field acoustic microphone and the thin-walled structure 14 can be set to 0.5 mm to 1 mm. By setting a reasonable distance, the measurement accuracy of the pressure field acoustic sensor can be improved.

[0045] The acoustic sensor 30 is mounted on a test bracket 20 . The test bracket 20 includes a cover 21 , a cover bracket 22 , a height-adjustable support rod 23 , and a mounting base 24 .

[0046] The mounting base 24 is fixedly arranged on the table of the test site. In some embodiments, the mounting base 24 can adopt a frame structure, which can be fastened to the table of the test site by bolt connectors or the like.

[0047] The housing bracket 22 is mounted on the mounting base 24 via an adjustable-height support rod 23 provided on the upper end surface of the mounting base 24. The housing 21 is mounted on the upper end of the housing bracket 22. The height of the housing 21 can be adjusted via the adjustable-height support rod 23 to ensure that the axis of the housing 21 is concentric with the axis of the nozzle scale test piece 10. This ensures a uniform gap between the acoustic sensor 30 and the nozzle outer wall 11 and / or thin-wall structure 14 of the nozzle scale test piece 10, effectively supporting high-precision testing of the acoustic vibration response of the nozzle outer wall.

[0048] In some embodiments of the present application, the adjustable height support rod 23 is a group (i.e., multiple) of long screws and nut fasteners, which can be installed on the mounting base 24 according to certain rules, such as a three-point or four-point rectangular manner, to support the cover bracket 22.

[0049] In the present application, the shape and axial length of the cover are designed according to the frequency characteristics and wavelength of the jet noise radiation. The cover 21 is a frustum-shaped structure as a whole, which is adapted to the shape of the nozzle outer wall 11 or the thin-walled structure 14. The cover 21 is sleeved on the outside of the nozzle outer wall 11, and the acoustic sensor 30 is installed on the cover 21. Among them, the cover 21 adopts a hollow design, and hollow holes 211 are provided in the circumferential and / or axial directions. By adopting a hollow design, the cover 21 has good low reflection and high transmission characteristics, and the noise reflection area is minimized to the maximum extent. Only the position for installing the acoustic sensor 30 and the cover bracket 22 is retained, thereby reducing the impact of the cover 21 on noise reflection. In some embodiments of the present application, the hollow hole 211 is a rectangular rounded structure or a trapezoidal rounded structure.

[0050] Furthermore, in order to reduce the effect of the bracket on noise reflection during the test, the surface of the cover 21 is subjected to sound absorption treatment. For example, the surface of the cover 21 can be coated with sound absorption paint to improve the sound absorption capacity of the cover 21.

[0051] The acoustic sensor 30 is installed on the cover 21 using a threaded structure. By adjusting the screw-in length of the thread, the distance between the acoustic sensor 30 and the nozzle outer wall 11 and / or the thin-walled structure 14 can be precisely adjusted to improve the measurement accuracy of the acoustic sensor 30.

[0052] In some embodiments of the present application, the cover 21, the cover bracket 22 and the mounting base 24 can be made of metal materials, such as Q45 steel, which can provide better mechanical properties and reduce costs.

[0053] Based on the nozzle surface acoustic load structural response test device 100 described above, the present application further provides a nozzle surface acoustic load structural response test method, which includes the following steps:

[0054] S10, first assemble the test bracket 20, fasten the mounting base 24 to the table of the test site through bolt connectors, and install the adjustable height support rod 23, the cover bracket 22 and the cover 21 on the mounting base 24 in sequence;

[0055] S20, inserting the nozzle scale test piece 10 into the cover 21 of the test stand 20, so that the axis of the nozzle scale test piece 10 roughly coincides with the axis of the cover 21 of the test stand 20;

[0056] S30, mounting the acoustic sensor 30 on the cover 21, adjusting the height of the acoustic sensor 30 using the height-adjustable support rod 23, and using the threaded structure between the acoustic sensor 30 and the cover 21 so that the distance between each acoustic sensor 30 and the nozzle outer wall 11 or the thin-wall structure 14 is substantially the same;

[0057] S40, strain gauges are arranged on the surface of the nozzle outer wall 11 to form dynamic stress measurement points to test the acoustic vibration response of the nozzle outer wall. The distribution of the dynamic stress measurement points covers the surface of the nozzle outer wall 11, and the positions of the dynamic stress measurement points are obtained based on the modal simulation results of the nozzle outer wall surface of the nozzle scale test piece 10 in a constrained state. The size of the strain gauges is minimized.

[0058] S50, perform acoustic vibration response test and analysis on the outer wall of the nozzle, use the tapping method to perform modal tapping on the surface of the outer wall 11 of the nozzle, use a unified dynamic test platform (or test software) to test and analyze the acoustic load and dynamic stress measurement points of the nozzle scale test piece 10, use the cross-spectrum analysis technology to perform correlation analysis on the acoustic load peak frequency band and the dynamic stress response frequency band of the nozzle scale test piece 10, so as to obtain the acoustic load distribution and acoustic vibration response characteristics of the nozzle scale test piece 10, and finally obtain the acoustic vibration response characteristics of the real nozzle through the acoustic vibration response characteristics of the nozzle scale test piece, providing technical and methodological support for nozzle structure design and acoustic fatigue control and suppression.

[0059] The testing method of the present application reduces the interference of the internal airflow and equipment vibration of the nozzle on the acoustic load test of the jet outer wall through a thin-wall structure based on the equivalent acoustic load and acoustic vibration response of the nozzle outer wall of a nozzle scale test piece with similar structure, realizes the acoustic load test of the nozzle outer wall through a non-contact pressure field testing method, and optimizes the layout scheme of the dynamic stress test of the nozzle outer wall by combining simulation and tapping. Finally, the acoustic load distribution and acoustic vibration response characteristics of the nozzle surface are obtained through a unified dynamic testing platform, which solves the problem of nozzle acoustic vibration response testing and analysis, and provides method support for nozzle structure design and acoustic fatigue suppression.

[0060] The above description is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in this application should be included in the scope of protection of the present application. Therefore, the scope of protection of the present application should be based on the scope of protection of the claims.

Claims

1. A nozzle surface acoustic load structural response test device, characterized in that: include: A scaled-down nozzle test piece, comprising a nozzle outer wall and a nozzle inner wall, wherein an outer duct is formed between the nozzle outer wall and the nozzle inner wall, and a thin-walled structure is provided on an outer surface of the nozzle outer wall on a rear side of an airflow path, and a hollow structure is formed between the thin-walled structure and the nozzle outer wall; A test bracket, which is mounted on a test site table and at least partially covers the thin-walled structure on the outer wall of the nozzle; The acoustic sensor is installed on the test bracket and is used to obtain the acoustic load distribution and acoustic vibration response characteristics of the nozzle scale test piece.

2. The nozzle surface acoustic load structural response testing device according to claim 1, characterized in that: The axial length of the thin-wall structure at least partially covers the outer surface of the nozzle outer wall corresponding to the end position of the nozzle inner wall.

3. The nozzle surface acoustic load structural response testing device according to claim 1, characterized in that: The material of the thin-wall structure is the same as that of the outer wall of the nozzle.

4. The nozzle surface acoustic load structural response testing device according to claim 3, characterized in that: The thickness of the thin-wall structure is 0.3 mm to 0.5 mm.

5. The nozzle surface acoustic load structural response testing device according to any one of claims 1 to 4, characterized in that: The test bracket includes a cover, a cover bracket, an adjustable height support rod and a mounting base. The mounting base is fixed to the test site platform through a connecting piece, the adjustable height support rod is installed on the mounting base, the cover is fixed to the adjustable height support rod through the cover bracket, and the acoustic sensor is installed on the cover. The height of the cover is adjusted by the adjustable height support rod to make the relative gap between the acoustic sensor and the nozzle outer wall and / or thin-wall structure of the nozzle scale test piece uniform.

6. The nozzle surface acoustic load structural response testing device according to claim 5, characterized in that: The cover shell has hollow holes in the circumferential direction and / or the axial direction, so that the cover shell has low reflection and high transmission characteristics.

7. The nozzle surface acoustic load structural response testing device according to claim 5 or 6, characterized in that: The surface of the cover shell is subjected to sound absorption treatment.

8. The nozzle surface acoustic load structural response testing device according to claim 5, characterized in that: The acoustic sensor is mounted on the cover of the test stand via a threaded structure, and the threaded structure enables the distance between the acoustic sensor and the cover to be adjustable.

9. The nozzle surface acoustic load structural response testing device according to claim 8, characterized in that: The distance between the acoustic microphone and the outer wall of the nozzle and / or the thin-wall structure is 0.5 mm to 1 mm.

10. A method for performing a nozzle surface acoustic load structural response test using the nozzle surface acoustic load structural response test device according to any one of claims 1 to 9, characterized in that: The method comprises: S10, assembling the test stand, fastening the mounting base of the test stand to the table surface of the test site through a connector, and sequentially installing an adjustable height support rod, a cover bracket, and a cover on the mounting base; S20, inserting the nozzle scale test piece into a cover of a test stand so that the axis of the nozzle scale test piece coincides with the axis of the cover of the test stand; S30, mounting the acoustic sensors on the housing, adjusting the height of the acoustic sensors using an adjustable height support rod, and adjusting the relative position between the acoustic sensors and the housing so that the distance between each acoustic sensor and the nozzle outer wall or thin-wall structure is the same and is a predetermined value; S40, arranging strain gauges on the surface of the nozzle outer wall to form dynamic stress measuring points, wherein the distribution of the dynamic stress measuring points covers the surface of the nozzle outer wall; S50, a tapping method is used to perform modal tapping on the outer wall surface of the nozzle, and a unified dynamic test platform is used to test and analyze the acoustic load and dynamic stress measurement points of the nozzle scale test piece. The cross-spectrum analysis technology is used to perform correlation analysis on the acoustic load peak frequency band and dynamic stress response frequency band of the nozzle scale test piece, thereby obtaining the acoustic load distribution and acoustic vibration response characteristics of the nozzle scale test piece. Finally, the acoustic vibration response characteristics of the real nozzle are obtained through the acoustic vibration response characteristics of the nozzle scale test piece.

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