Leak hole jet noise test device and test method

Abstract

The application discloses a leakage hole jet flow noise testing device and testing method, which is used for simulating jet flow noise at different shaped leakage holes under different flow rates, and collecting sound emission signals of the noise; the testing device comprises a gas conveying unit, a flow rate control unit and a leakage hole simulation unit; the gas conveying unit is used for providing gas flow simulating fluid in actual working conditions; the flow rate control unit is used for simulating different flow rates of the gas flow by adjusting the flow of the gas flow; the leakage hole simulation unit is provided with a detachable panel at the end of a gas conveying pipeline, and the panel is provided with through holes for simulating different shaped leakage holes; and a sound emission sensor is arranged around the through holes and used for collecting noise signals of jet flow of the gas flow at the through holes. The leakage hole jet flow noise testing device and testing method can test noises of different shaped leakage holes under different flow rates, and provide a basis for identifying fault signals of the leakage holes with different flow rates and different shapes.

Description

Technical Field

[0001] This invention relates to the field of safety monitoring technology for petrochemical equipment, and in particular to a test device and method for testing the noise of jets from a leaking hole. Background Technology

[0002] Leakage is a major form of process equipment failure, causing fluid media to leak and creating safety hazards. In the petrochemical industry, leaks can occur at any stage of production, transportation, storage, operation, use, and waste disposal. Common leak sources include pinhole leaks and large-area leaks; common leak source models include seepage, leakage, and venting. Most materials possess flammable, explosive, or toxic and hazardous properties; once a leak occurs for any reason, it can easily lead to a serious accident. Therefore, the detection of leaks is crucial. In common leakage accidents, leaks often form in components such as pipes and nozzles where there is a scouring effect from the medium.

[0003] Acoustic emission (AE) is the phenomenon of transient elastic stress waves emitted by a material due to the rapid release of energy in a localized area. AE detection technology can be used to detect the presence of leaks. When a leak occurs in the equipment, the friction between the leaking medium and the leak hole generates an acoustic emission signal. Field testing environments are complex, requiring the ability to identify leak signals from numerous sources. This necessitates simulation experiments to obtain the jet noise from leaks under different conditions and to understand the signal characteristics.

[0004] Therefore, there is an urgent need for a noise testing device that, combined with acoustic emission technology, can simulate high-velocity (different flow rates) environments to test the jet noise of leak holes of different shapes and obtain leakage characteristic signals. This provides a basis for identifying fault signals of leak holes in different states and judging equipment damage caused by different production processes. It also proposes specific indicators for the safe range of leak hole perforation size during operation, playing a role in ensuring normal operation under actual working conditions.

[0005] The information disclosed in this background section is intended only to enhance the understanding of the overall background of the invention and should not be construed as an admission or in any way implying that the information constitutes prior art known to those skilled in the art. Summary of the Invention

[0006] The purpose of this invention is to provide a device and method for testing the noise of leak holes, which can perform noise tests on leak holes of different shapes at different flow rates, and provide a basis for identifying fault signals of leak holes of different shapes at different flow rates.

[0007] To achieve the above objectives, according to a first aspect of the present invention, the present invention provides a leak hole jet noise testing device for simulating jet noise at leak holes of different shapes at different flow velocities and collecting acoustic emission signals of the noise; comprising: a gas delivery unit for providing airflow to simulate fluid in actual working conditions; a flow rate control unit for adjusting the flow rate of the simulated airflow to different flow velocities; a leak hole simulation unit having a detachable panel at the end of the gas delivery pipeline, the panel having through holes for simulating leak holes of different shapes; and an acoustic emission sensor arranged around the through holes for collecting noise signals of the airflow jet at the through holes.

[0008] Furthermore, in the above technical solution, the gas transmission pipeline can be composed of a main pipeline and multiple branch pipelines, and the gas flow rate in each branch pipeline can be controlled independently.

[0009] Furthermore, in the above technical solution, the branch pipe may include: a first branch pipe, wherein the through hole on the detachable panel at its end is exposed to simulate an external wall leakage hole in actual working conditions; and a second branch pipe, wherein the through hole on the detachable panel at its end is closed to simulate an internal wall leakage hole in actual working conditions.

[0010] Furthermore, in the above technical solution, the main pipeline is a telescopic pipeline, used to adjust the distance between the through holes at the ends of each branch pipeline, in order to simulate multiple adjacent leakage holes that occur simultaneously under actual working conditions.

[0011] Furthermore, in the above technical solution, the gas transmission unit may include a fan and a buffer tank. The airflow generated by the fan enters the buffer tank, which is connected to the main pipeline through a first passage and a second passage respectively. A first flow meter is provided on the first passage, which is connected to the main pipeline through a first valve. A second flow meter is provided on the second passage, which is directly connected to the main pipeline.

[0012] Furthermore, in the above technical solution, the detection range of the first flow meter is 0-10m. 3 / h; the detection range of the second flow meter is 0-40m 3 / h.

[0013] Furthermore, in the above technical solution, the leakage hole simulation unit can be designed as a cylindrical hollow structure, and the detachable panel is located on the top of the cylindrical hollow structure and fixed with bolts.

[0014] Furthermore, in the above technical solution, the exposed through hole at the end of the first branch pipe is located in the center of the detachable panel, and the corresponding acoustic emission sensor is located on the outer edge of the detachable panel; the closed through hole at the end of the second branch pipe is located in the center of the detachable panel and is covered by a cover; the corresponding acoustic emission sensor can be located on the upper surface of the cover.

[0015] According to a second aspect of the present invention, the present invention provides a method for testing the jet noise of a leaking hole, comprising the following steps: A. constructing a test pipeline and testing the airtightness of the pipeline and the normal operating conditions of the flow meter and acoustic emission sensor; B. connecting a first passage, allowing the airflow to run at a low velocity to an exposed through-hole at the end of a first branch pipe, simulating an external wall leaking hole through the exposed through-hole, and collecting the acoustic emission signal at the exposed through-hole; and / or, allowing the airflow to run at a low velocity to a closed through-hole at the end of a second branch pipe, simulating an internal wall leaking hole through the closed through-hole, and collecting the acoustic emission signal at the closed through-hole.

[0016] Furthermore, in the above technical solution, the method may further include step C: closing the first passage and connecting the second passage, so that the airflow runs at a high velocity to the exposed through hole at the end of the first branch pipe, and collects the acoustic emission signal at the exposed through hole to simulate an outer wall leakage hole; and / or, so that the airflow runs at a high velocity to the closed through hole at the end of the second branch pipe, and collects the acoustic emission signal at the closed through hole to simulate an inner wall leakage hole.

[0017] Furthermore, in the above technical solution, the exposed and closed through holes of different shapes can be replaced by detachable panels at the ends of the first and second branch pipes.

[0018] Furthermore, in the above technical solution, the first passage can detect the flow rate through the first flow meter, and control the airflow velocity of the main pipe through the first valve, and further control the flow velocity at the through hole through the valves on the first branch pipe and / or the second branch pipe, so that the airflow at the through hole is in a low-speed state.

[0019] Furthermore, in the above technical solution, the second passage detects the flow rate through a second flow meter, and controls the flow velocity at the through hole through valves on the first branch pipe and / or the second branch pipe, so that the airflow at the through hole is in a high-speed state.

[0020] Furthermore, in the above technical solution, the method may also include: adjusting the distance between the through holes at the ends of each branch pipeline to simulate multiple adjacent leakage holes that occur simultaneously under actual working conditions.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] 1) This invention can simulate the noise of a leak hole in a pipeline or nozzle under actual working conditions and collect the acoustic emission signal of the noise; it can be used to monitor the fault situation in a timely and real-time manner when a leak hole suddenly appears in certain easily worn parts, and can solve the complex problem that leak holes cannot be directly detected in actual industrial working conditions.

[0023] 2) This invention utilizes the combination of acoustics and flow field to reflect the situation of different flow velocities and different leakage hole shapes in real time, predict leakage hole failures, thereby reducing unnecessary consumption, which is of great significance for ensuring the stable operation of production;

[0024] 3) The multiple branch pipes of this invention can simulate leakage holes at different locations at the end of each branch pipe, i.e., external or internal wall leakage holes under actual working conditions; or they can simulate leakage holes of different shapes at the end of each branch pipe. This allows for continuous testing without the need for disassembly and replacement after testing the noise of a simulated leakage hole.

[0025] 4) The first and second pathways of the present invention can be selected according to different testing needs, and can be switched between a large flow rate range and a small flow rate range.

[0026] 5) This invention can obtain simulated leak holes with different spacing at the same time through the telescopic main pipe, which can simulate multiple adjacent leak holes that appear simultaneously under actual working conditions; when collecting acoustic emission signals, the superimposed signals can be collected by an acoustic emission sensor arranged at one of the simulated leak holes.

[0027] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it according to the contents of the specification, and to make the above and other objects, technical features and advantages of the present invention easier to understand, one or more preferred embodiments are listed below and described in detail with reference to the accompanying drawings. Attached Figure Description

[0028] Figure 1 This is a three-dimensional structural schematic diagram of the leakage hole jet noise testing device of the present invention.

[0029] Figure 2 This is a side view schematic diagram of the leakage hole jet noise testing device of the present invention.

[0030] Figure 3 This is a schematic diagram of the structure of the leakage hole simulation unit of the present invention, simulating a leakage hole on the outer wall.

[0031] Figure 4 This is a schematic diagram of the structure of the leakage hole simulation unit of the present invention, simulating the leakage hole in the inner wall.

[0032] Explanation of key figure labels:

[0033] 1-Fan, 2-Buffer tank, 3-First flow meter, 4-First valve, 5-Main pipe, 6-Second flow meter, 7-High flow pipe, 8-Branch pipe valve, 9-Cylindrical hollow structure, 91-Removable panel, 910-Through hole, 911-Bolt hole, 92-Cover, 10-Base, 101-Pulley, 11-Vertical retainer, 12-Horizontal retainer. Detailed Implementation

[0034] The specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings, but it should be understood that the scope of protection of the present invention is not limited to the specific embodiments.

[0035] Unless otherwise expressly stated, throughout the specification and claims, the term "comprising" or its variations such as "including" or "comprises" shall be understood to include the stated elements or components without excluding other elements or other components.

[0036] In this document, for ease of description, spatial relative terms such as “below,” “under,” “down,” “above,” “above,” “upper,” etc., are used to describe the relationship of one element or feature to another element or feature in the accompanying drawings. It should be understood that spatial relative terms are intended to encompass different orientations of an object in use or operation, in addition to those depicted in the figures. For example, if an object in the figure is flipped, an element described as “below” or “under” another element or feature would be oriented “above” that element or feature. Thus, the exemplary term “below” can encompass both the downward and upward orientations. An object may also have other orientations (rotated 90 degrees or other orientations), and the spatial relative terms used herein should be interpreted accordingly.

[0037] In this document, the terms "first," "second," etc., are used to distinguish two different elements or parts, and are not used to define specific positions or relative relationships. In other words, in some embodiments, the terms "first," "second," etc., can also be used interchangeably.

[0038] The leakage hole jet noise testing device and corresponding testing method of this invention can simulate the noise of leakage holes in pipelines or nozzles under actual working conditions and collect the acoustic emission signals of the noise. It can be used to promptly and in real-time monitor fault conditions when leakage holes suddenly appear in certain easily worn parts, solving the complex problem of not being able to directly detect leakage holes in actual industrial conditions. This invention utilizes the combination of acoustics and flow field to achieve real-time online reflection of different flow velocities and leakage hole shapes, predicting leakage hole faults, thereby reducing unnecessary consumption and playing a significant role in ensuring stable production operation.

[0039] Example 1

[0040] The leak hole jet noise testing device of this embodiment is used to collect the acoustic emission signal of the noise by simulating jet noise at leak holes of different shapes at different flow velocities. It includes: a gas delivery unit, a flow rate control unit, a leak hole simulation unit, and an acoustic emission sensor. The gas delivery unit provides airflow to simulate the fluid in actual working conditions. Figure 1 , 2 As shown, the gas delivery unit specifically includes a blower 1, a buffer tank 2, and corresponding pipelines. The blower 1 and the buffer tank 2 are connected by pipelines, and are mounted on a base 10 via a matching fixed frame. Rollers 101 are installed at the bottom of the base 10 to facilitate the overall movement of the testing device. The corresponding pipelines include a main pipe 5 and multiple branch pipes connected to the main pipe 5. The multiple branch pipes can simulate leaks at different locations (e.g., external or internal wall leaks under actual working conditions) at the end of each branch pipe, and can also simulate leaks of different shapes at the end of each branch pipe (leaks caused by erosion will have various shapes due to the erosion characteristics of different parts). This allows for uninterrupted testing, eliminating the need for disassembly and replacement after testing the noise of a simulated leak.

[0041] Further as Figure 1 , 2 As shown, two passages are provided between the buffer tank 2 and the main pipeline 5: a first passage and a second passage. The first passage is equipped with a first flow meter 3 and a first valve 4. This first passage is used to provide a low-velocity airflow, and the detection range of the first flow meter 3 is 0-10m. 3 / h, the first valve 4 controls the airflow rate and velocity entering the main pipe 5. A second flow meter 6 is installed in the second passage, and the second flow meter 6 is directly connected to the main pipe 5 through a high-flow pipe 7 (without a valve). The detection range of the second flow meter 6 is 0-40m. 3 / h, allowing the airflow entering the main duct 5 to achieve a higher velocity. The first and second pathways can be selected according to different testing needs, switching between high and low velocity ranges. Further, as... Figure 1 As shown, each branch pipe of the main pipe 5 can be equipped with a corresponding branch pipe valve 8, which can independently control the start and stop of each branch pipe and further adjust the flow velocity on each branch pipe as needed. The first flow meter 3, the second flow meter 6, and the valves in the pipeline constitute the flow velocity control unit of the present invention. This flow velocity control unit can simulate different flow velocities of the airflow by adjusting the flow rate of the airflow. The two passages can simulate airflows with different flow velocity ranges respectively. The two ends of the flow meters and valves are connected to the pipeline through flanges. Preferably, but not limitingly, the first valve 4 can be a small ball valve; the valves 8 of each branch pipe can be large ball valves.

[0042] Further as Figure 1 , 2 As shown, the leak hole simulation unit in the test device of this embodiment can be connected to the end of each branch pipe via a short pipe. The leak hole simulation unit is a cylindrical hollow structure 9. Further reference... Figure 3 The cylindrical hollow structure 9 can be made of plexiglass. A detachable panel 91 is located at the top of the gas pipeline. This detachable panel 91 is also made of plexiglass and has bolt holes 911 along its outer edge for fixing and detachment. Through holes 910 are provided on the panel to simulate leak holes of different shapes. Figure 3 The diagram shows a circular hole, but the shape of the through hole 910 can be any leakage hole shape generated in actual working conditions.

[0043] The testing device of this invention collects acoustic emission signals of simulated leak holes of different shapes and flow rates. Therefore, an acoustic emission sensor (not shown in the figure) needs to be placed around the through-hole 910; in this embodiment, it can be placed at the outer edge of the detachable panel 91. This sensor is used to collect noise signals from the airflow jet at the through-hole. Subsequently, the collected acoustic signals can be integrated using the acoustic emission signal data corresponding to the simulated leak holes, and time-frequency domain feature parameters can be extracted. The analyzed signal acoustic signature feature parameters (i.e., Mel-frequency cepstral coefficients (MFCC)) are used as input variables for an artificial neural network model and a Gaussian mixture model for model training, providing a basis for identifying fault signals from leak holes of different flow rates and shapes in the future.

[0044] Further as Figure 1 , 2 As shown, in order to simulate leakage holes at different locations (i.e., leakage holes on the outer wall and inner wall of the pipe or nozzle), this embodiment sets up a first branch pipe (i.e., the second from the left among five branch pipes) and a second branch pipe (i.e., the fourth from the left among five branch pipes). The through hole 910 on the removable panel 91 at the end of the first branch pipe is exposed (see reference). Figure 3 This is used to simulate an external wall leakage hole in actual working conditions. The through hole 910 on the removable panel 91 at the end of the second branch pipe is in a closed state (reference). Figure 4 This is used to simulate an internal wall leakage hole in actual working conditions. In this embodiment, a cover 92 is provided on the removable panel 91 to seal the through hole 910. Preferably, but not limitingly, for... Figure 4 The simulated internal wall leakage hole allows acoustic emission sensors to be mounted on the upper surface of the enclosure 92. (Reference) Figure 3 , Figure 4The exposed through hole 910 at the end of the first branch pipe is located in the center of the detachable panel 91, and the corresponding acoustic emission sensor is located on the outer edge of the detachable panel 91; the closed through hole 910 at the end of the second branch pipe is located in the center of the detachable panel 91 and is covered by the cover 92; the corresponding acoustic emission sensor is located on the upper surface of the cover 92.

[0045] Example 2

[0046] Similar to Example 1, the leak hole jet noise testing device in this example is also used to collect acoustic emission signals of noise by simulating jet noise at leak holes of different shapes at different flow velocities. The testing device in Example 2 also includes: a gas delivery unit, a flow rate control unit, a leak hole simulation unit, and an acoustic emission sensor (the functions, specific structures, and connection relationships of each unit are not described here). Unlike Example 1, the main pipe 5 in Example 1 can be set as a telescopic pipe. The telescopic pipe can be used to adjust the distance between the through holes (i.e., simulated leak holes) at the ends of each branch pipe. Considering that the situation of leak holes is more complex in actual working conditions, when multiple leak holes appear in adjacent locations, their acoustic emission signals will have a superposition effect. Therefore, without testing such situations and subsequent model training, it will be impossible to accurately identify the location and shape of the leak hole corresponding to the acoustic emission signal with superposition effect. Therefore, this example uses a telescopic main pipe to obtain simulated leak holes with different spacing at the same time, which can simulate multiple adjacent leak holes that appear simultaneously in actual working conditions. During acoustic emission signal acquisition, the superimposed signal can be collected by an acoustic emission sensor placed at one of the simulated leak holes.

[0047] Example 3

[0048] This embodiment is an example of a test method for testing the jet noise of a leak hole, providing a test method using the test device built in embodiment 1.

[0049] Step S101: Check the complete connection of the entire device in Example 1, and whether there is any damage to each connecting component. Check the airtightness of the entire device by starting the fan 1. Check whether the first flow meter 3 and the second flow meter 6 are in normal working condition. Check whether the first valve 4 and the valves 8 of each branch pipeline can work normally to control the flow rate and velocity in the pipeline, and ensure that the test can be carried out normally. First, perform a calibration lead breakage test at the acoustic emission sensors arranged at the end of each branch pipeline on the main pipeline 5 to ensure that each sensor can collect acoustic emission signals normally, and ensure that the test can be carried out normally.

[0050] Step S102: Connect the first passage, so that the airflow runs at a low velocity to the exposed through hole at the end of the first branch pipe, and collect the acoustic emission signal at the exposed through hole to simulate an outer wall leakage hole; and / or, so that the airflow runs at a low velocity to the closed through hole at the end of the second branch pipe, and collect the acoustic emission signal at the closed through hole to simulate an inner wall leakage hole.

[0051] Specifically, this step involves collecting acoustic emission signals at a simulated leak hole under low flow rate conditions. Before the test begins, the first valve 4 in the first passage and the valves 8 in each branch pipe are adjusted to zero the flow values ​​of the first flow meter 3 and the second flow meter 6. At the start of the test, the switches of the fan 1 and the connected buffer tank 2 are turned on, and the first passage is opened. The flow rate in the main pipe 5 is controlled by controlling the first valve 4 as needed. A detachable panel 91 made of plexiglass (with the through hole in the center of the panel exposed to simulate an external wall leak hole) is installed at the end of the first branch pipe as needed. The valve 8 on the first branch pipe is opened, and the acoustic emission acquisition system is turned on simultaneously. This allows the acoustic emission signal at the simulated external wall leak hole to be collected. Since there are various perforations or gaps in actual industrial leak holes, the detachable panel 91 made of plexiglass can be replaced as needed. The specific operation is to close the valve 8 on the first branch pipe, replace the panel where the leak hole that has been tested is located, replace the panel that will be tested, and then open the valve 8 on the first branch pipe again, while simultaneously turning on the acoustic emission acquisition system.

[0052] Furthermore, with valve 8 on the first branch pipe closed and the first passage still open, valve 8 on the second branch pipe is opened, and the acoustic emission acquisition system is activated simultaneously. This allows the acquisition of acoustic emission signals at the simulated inner wall leak (the acoustic emission sensor is positioned on the upper surface of the cover 92 used to seal the leak). The specific operation of replacing the detachable panel 91 made of plexiglass material inside the cover 92 is as described above, thereby simulating a leak fault on the inner wall. Since the simulated outer wall leak and inner wall leak are located at the ends of the first and second branch pipes respectively and can be controlled independently, the two tests in this step can be performed consecutively.

[0053] Step S103: Close the first passage and connect the second passage, so that the airflow runs at a high velocity to the exposed through hole at the end of the first branch pipe, and the exposed through hole simulates an outer wall leakage hole, and the acoustic emission signal at the exposed through hole is collected; and / or, so that the airflow runs at a high velocity to the closed through hole at the end of the second branch pipe, and the closed through hole simulates an inner wall leakage hole, and the acoustic emission signal at the closed through hole is collected.

[0054] Specifically, this step involves collecting noise emission signals at a simulated leak hole under high flow velocity conditions. First, the first valve 4 is closed to shut off the first passage, making the first flow meter scale zero and the second passage open. At the start of the test, the flow velocity in the corresponding branch pipe is directly controlled by the valves 8 of each branch pipe. The specific test method is the same as step S102 and will not be repeated here.

[0055] Example 4

[0056] This embodiment is an example of a test method for testing the jet noise of a leak hole, providing a test method using a test device built according to embodiment 2.

[0057] Unlike Example 3, the main pipe 5 constructed in Example 3 can be configured as a telescopic pipe. The telescopic pipe can be used to adjust the distance between the through holes (i.e., simulated leak holes) at the ends of each branch pipe. Considering that the situation of leak holes is complex in actual working conditions, when multiple leak holes appear in adjacent locations, their acoustic emission signals will have a superposition effect. Therefore, without testing such situations and subsequent model training, it will be impossible to accurately identify the location and shape of the leak hole corresponding to the superimposed acoustic emission signal. Therefore, this example replaces the main pipe with a telescopic pipe, which can obtain simulated leak holes with different spacings at the same time, simulating multiple adjacent leak holes appearing simultaneously in actual working conditions. Specifically, firstly, the telescopicity of the telescopic main pipe is adjusted as needed so that the distance between the simulated leak holes at the ends of two or more branch pipes meets the preset distance requirement. The two or more simulated leak holes can all be exposed through holes, all be closed through holes, or a combination of both. During acoustic emission signal acquisition, the superimposed signal can be collected by an acoustic emission sensor placed at one of the simulated leak holes.

[0058] The foregoing description of specific exemplary embodiments of the present invention is for illustrative and explanatory purposes. These descriptions are not intended to limit the invention to the precise forms disclosed, and it will be apparent that many changes and variations can be made in accordance with the foregoing teachings. The exemplary embodiments were chosen and described in order to explain the specific principles of the invention and its practical application, thereby enabling those skilled in the art to implement and utilize various different exemplary embodiments of the invention, as well as various different choices and variations. Any simple modifications, equivalent changes, and alterations made to the foregoing exemplary embodiments should fall within the scope of protection of the present invention.

Claims

1. A leaky hole jet noise test device, characterized by, Acquisition of acoustic emission signals of the noise by simulating jet noise at leak holes of different shapes at different flow velocities; including: The gas delivery unit is used to provide airflow to simulate the fluid in actual working conditions; A flow rate control unit that simulates different flow rates of airflow by adjusting the flow rate of the airflow; A leakage hole simulation unit has a detachable panel at the end of the gas pipeline, with through holes on the panel to simulate leakage holes of different shapes. The gas pipeline consists of a main pipeline and multiple branch pipelines, with the airflow velocity in each branch pipeline controlled independently. The branch pipelines include: a first branch pipeline, whose through holes on the detachable panel at its end are exposed to simulate external wall leakage holes in actual operating conditions; and a second branch pipeline, whose through holes on the detachable panel at its end are closed to simulate internal wall leakage holes in actual operating conditions. The main pipeline is a telescopic pipeline used to adjust the distance between the through holes at the ends of each branch pipeline to simulate multiple adjacent leakage holes occurring simultaneously in actual operating conditions. An acoustic emission sensor, arranged around the through-hole, is used to collect noise signals from the airflow jet at the through-hole.

2. The leak hole jet noise test device of claim 1, wherein, The gas delivery unit includes a fan and a buffer tank. The airflow generated by the fan enters the buffer tank, which is connected to the main pipeline through a first passage and a second passage respectively. A first flow meter is provided on the first passage, and the first flow meter is connected to the main pipeline through a first valve. A second flow meter is provided on the second passage, and the second flow meter is directly connected to the main pipeline.

3. The leak hole jet noise test device of claim 2, wherein, The detection range of the first flow meter is 0-10 m 3 / h; the detection range of the second flow meter is 0-40 m 3 / h.

4. The leak hole jet noise test device of claim 1, wherein, The leakage hole simulation unit is a cylindrical hollow structure, and the detachable panel is located on top of the cylindrical hollow structure and is fixed with bolts.

5. The leak hole jet noise test device of claim 4, wherein, The exposed through hole at the end of the first branch pipe is located in the center of the removable panel, and the corresponding acoustic emission sensor is located on the outer edge of the removable panel; the closed through hole at the end of the second branch pipe is located in the center of the removable panel and is covered by a cover; the corresponding acoustic emission sensor is located on the upper surface of the cover.

6. A method of leaky hole jet noise testing, characterized in that, Using the apparatus as described in claim 2 includes the following steps: A. Set up the test pipeline and check the airtightness of the pipeline and ensure that the flow meter and acoustic emission sensor are in normal working condition. B. Connect the first passage, allowing the airflow to run at a low velocity to the exposed through-hole at the end of the first branch pipe, simulating an outer wall leakage hole through the exposed through-hole, and collect the acoustic emission signal at the exposed through-hole; and / or, allow the airflow to run at a low velocity to the closed through-hole at the end of the second branch pipe, simulating an inner wall leakage hole through the closed through-hole, and collect the acoustic emission signal at the closed through-hole.

7. The leak hole plume noise test method of claim 6, wherein, It also includes step C: closing the first passage and connecting the second passage, so that the airflow runs at a high velocity to the exposed through hole at the end of the first branch pipe, and the exposed through hole simulates an outer wall leakage hole, and the acoustic emission signal at the exposed through hole is collected; and / or, so that the airflow runs at a high velocity to the closed through hole at the end of the second branch pipe, and the closed through hole simulates an inner wall leakage hole, and the acoustic emission signal at the closed through hole is collected.

8. The leak hole plume noise test method of claim 6 or 7, wherein, The exposed through-hole and the closed through-hole can be replaced with different shapes by using the removable panels at the ends of the first and second branch pipes.

9. The leak hole plume noise test method of claim 8, wherein, The first passage detects the flow rate through a first flow meter, controls the airflow velocity in the main pipe through a first valve, and further controls the flow velocity at the through hole through valves on the first branch pipe and / or the second branch pipe, so that the airflow at the through hole is in a low-speed state.

10. The leak hole plume noise test method of claim 8, wherein, The second passage detects the flow rate through a second flow meter and controls the flow velocity at the through hole through valves on the first branch pipe and / or the second branch pipe, so that the airflow at the through hole is in a high-speed state.

11. The leak hole jet noise test method of claim 8, wherein, Also includes: Adjust the distance between the through holes at the ends of each branch pipe to simulate multiple adjacent leaks occurring simultaneously under actual working conditions.

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