Method, device and equipment for measuring sound insulation of pipe wall, and storage medium

Abstract

The application discloses a kind of pipeline wall sound insulation quantity measurement method, device, equipment and storage medium, which separates the incident wave sound pressure and reflected wave sound pressure in pipeline based on mathematical modeling, and is further decomposed into each order acoustic mode, by providing different sound source characteristics or pipeline inner end boundary condition, the coefficient of each order incident wave is solved, and the sound insulation quantity of each order acoustic mode is obtained according to the coefficient of each order incident wave, the interference of sound source characteristics and pipeline inner end boundary condition can be eliminated, the accurate measurement of the inherent properties of pipe wall sound insulation is realized, suitable for complex sound field environment (such as high-order mode dominant pipeline system), reliable sound insulation performance evaluation standard can be provided for industry.

Description

Technical Field

[0001] This invention belongs to the field of acoustic testing technology, and in particular relates to a method, device, equipment and storage medium for measuring the sound insulation of pipe walls. Background Technology

[0002] In the field of pipeline engineering and noise control, the sound insulation performance of pipelines is one of the key indicators for evaluating the quality of pipeline products and the noise reduction effect of engineering. The accuracy of its testing directly affects the selection of pipelines, design optimization and the formulation of noise control schemes.

[0003] Currently, traditional methods for testing pipe sound insulation in the industry typically involve placing a small number of microphones at corresponding locations inside and outside the pipe under test. The microphones collect sound pressure signals from inside and outside the pipe, and then the average sound pressure level is calculated. The difference between these average sound pressure levels is used as the core criterion for evaluating the pipe's sound insulation performance. However, the test results obtained using this method are significantly affected by the characteristics of the sound source inside the pipe or the boundary conditions at the pipe's end, lacking repeatability and accuracy. Summary of the Invention

[0004] Based on this, and in response to the aforementioned technical problems, a method, apparatus, equipment, and storage medium for measuring the sound insulation of pipe walls are provided.

[0005] The technical solution adopted in this invention is as follows:

[0006] As a first aspect of the present invention, a method for measuring the sound insulation of a pipe wall is provided, characterized in that it includes:

[0007] Modeling the sound field inside the pipe: For the sound pressure at any point inside the circular pipe, considering the incident and reflected waves, the expansion using Bessel functions in cylindrical coordinates is as follows:

[0008] ,

[0009] in, Represents the coordinates of the pipeline. sound pressure, These represent the length, angle, and axial distance of the point along the circumferential radius, respectively. This represents the (m,n) order sound pressure along the axial incident direction. This represents the (m,n) order sound pressure along the axial reflection direction. It is the base of the natural logarithm. The wave number represents the (m, n)th acoustic mode, and i represents the imaginary unit. Represents the eigenfunctions, A represents the normalization parameter, and we take A=1. It is an m-th order Bessel function of the first kind;

[0010] Two million sound pressure tests were conducted, each with different pipe sound source characteristics or end boundary conditions. During each test, the sound pressure was measured from multiple microphones arranged in the upstream and downstream pipes of the pipe under test, and the sound pressure outside the pipe under test was also acquired. Where M is the order of the acoustic mode, and G microphones are arranged in the upstream and downstream pipes respectively, with the G microphones arranged along the circumference and axial direction of the corresponding pipes.

[0011] For the general case of using G microphones to separate a total of M acoustic modes, the following acoustic mode separation equations exist:

[0012] ,

[0013] The sound pressure level for each test was calculated based on the aforementioned acoustic mode separation equation. - Similarly, the transmitted wave and its reflected wave in the downstream pipeline are taken as the incident wave and reflected wave of the pipeline, and the sound pressure level for each test is calculated according to the aforementioned acoustic mode separation equation. - ,in, to This represents the sound pressure measured by the first to the Gth microphones in either the upstream or downstream pipe. Represents the sound pressure of the first-order incident wave. Represents the sound pressure of the Mth incident wave. Represents the sound pressure of the first-order reflected wave. Represents the sound pressure of the Mth order reflected wave. The eigenfunction matrix representing the acoustic modes;

[0014] Based on the sound pressure of 2M , - , - And the following equation, calculated to obtain :

[0015] ,

[0016] in, The coefficients representing the incident waves of each order. The coefficients representing the reflected sound at each order of transmitted sound;

[0017] Based on the calculation The sound insulation of the pipe wall under test in each acoustic mode is calculated using the following equation. :

[0018] .

[0019] As a second aspect of the present invention, a device for measuring the sound insulation of a pipe wall is provided, characterized in that it comprises:

[0020] The first module is used to model the sound field inside the pipe: For the sound pressure at any point inside the circular pipe, considering the incident wave and the reflected wave, the expansion using Bessel functions in cylindrical coordinates is as follows:

[0021] ,

[0022] in, Represents the coordinates of the pipeline. sound pressure, These represent the length, angle, and axial distance of the point along the circumferential radius, respectively. This represents the (m,n) order sound pressure along the axial incident direction. This represents the (m,n) order sound pressure along the axial reflection direction. It is the base of the natural logarithm. The wave number represents the (m, n)th acoustic mode, and i represents the imaginary unit. Represents the eigenfunctions, A represents the normalization parameter, and we take A=1. It is an m-th order Bessel function of the first kind;

[0023] The second module is used to perform 2M sound pressure tests. Each sound pressure test provides different pipe sound source characteristics or end boundary conditions. During each sound pressure test, the measured sound pressure is obtained from multiple microphones arranged in the upstream and downstream pipes of the pipe under test, and the sound pressure outside the pipe under test is also obtained. Where M is the order of the acoustic mode, and G microphones are arranged in the upstream and downstream pipes respectively, with the G microphones arranged along the circumference and axial direction of the corresponding pipes.

[0024] The third module is used for the general case of separating a total of M acoustic modes using G microphones, with the following acoustic mode separation equation:

[0025] ,

[0026] The sound pressure level for each test was calculated based on the aforementioned acoustic mode separation equation. - Similarly, the transmitted wave and its reflected wave in the downstream pipeline are taken as the incident wave and reflected wave of the pipeline, and the sound pressure level for each test is calculated according to the aforementioned acoustic mode separation equation. - ,in, to This represents the sound pressure measured by the first to the Gth microphones in either the upstream or downstream pipe. Represents the sound pressure of the first-order incident wave. Represents the sound pressure of the Mth incident wave. Represents the sound pressure of the first-order reflected wave. Represents the sound pressure of the Mth order reflected wave. The eigenfunction matrix representing the acoustic modes;

[0027] The fourth module is used to calculate the sound pressure levels of 2M units. , - , - And the following equation, calculated to obtain :

[0028] ,

[0029] in, The coefficients representing the incident waves of each order. The coefficients representing the reflected sound at each order of transmitted sound;

[0030] The fifth module is used to calculate... The sound insulation of the pipe wall under test in each acoustic mode is calculated using the following equation. :

[0031] .

[0032] As a third aspect of the present invention, an electronic device is provided, characterized in that it includes a storage module, the storage module including instructions loaded and executed by a processor, the instructions, when executed, causing the processor to perform a method for measuring the sound insulation of a pipe wall as described in the first aspect above.

[0033] As a fourth aspect of the present invention, a computer-readable storage medium is provided, the computer-readable storage medium storing one or more programs, characterized in that, when the one or more programs are executed by a processor, they implement the method for measuring the sound insulation of a pipe wall as described in the first aspect.

[0034] This invention separates the incident wave sound pressure and reflected wave sound pressure in a pipeline based on mathematical modeling, and further decomposes them into various sound modes. By providing different sound source characteristics or pipeline end boundary conditions, the coefficients of each incident wave are solved, and the sound insulation of each sound mode is obtained based on the coefficients of each incident wave. This can eliminate the interference of sound source characteristics and pipeline end boundary conditions, and realize the accurate measurement of the inherent sound insulation properties of the pipe wall. It is suitable for complex sound field environments (such as pipeline systems dominated by higher-order modes) and can provide the industry with a reliable sound insulation performance evaluation standard. Attached Figure Description

[0035] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments:

[0036] Figure 1 A flowchart of a method for measuring the sound insulation of a pipe wall provided in an embodiment of the present invention;

[0037] Figure 2 A schematic diagram of a device for measuring the sound insulation of a pipe wall provided in an embodiment of the present invention;

[0038] Figure 3 A schematic diagram of an electronic device provided in an embodiment of the present invention;

[0039] Figure 4 This is a schematic diagram of the sound pressure test in an embodiment of the present invention. Detailed Implementation

[0040] The embodiments of the present invention will be described below with reference to the accompanying drawings. It should be noted that the embodiments described in this specification are not exhaustive and do not represent the only embodiments of the present invention. The corresponding embodiments below are only for clearly illustrating the inventive content of this patent and are not intended to limit its implementation. For those skilled in the art, different variations and modifications can be made based on the embodiments described. Any variations or modifications that fall within the technical concept and inventive content of this invention and are obvious are also within the protection scope of this invention.

[0041] like Figure 1 As shown in the figure, this application provides a method for measuring the sound insulation of a pipe wall, the specific process of which is as follows:

[0042] S101. Modeling the sound field inside the pipe: Sound waves propagate in the impedance pipe, and the sound pressure satisfies the Helmholtz equation and rigid boundary conditions. The wall equation is independent of the propagation direction z. For the sound pressure at any point inside the circular pipe, considering the incident wave and the reflected wave, the following is obtained by expanding the equation using Bessel functions in cylindrical coordinates:

[0043] ,

[0044] in, Represents the coordinates of the pipeline. sound pressure, These represent the length, angle, and axial distance of the point along the circumferential radius, respectively. This represents the (m,n) order sound pressure along the axial incident direction. This represents the (m,n) order sound pressure along the axial reflection direction. It is the base of the natural logarithm (a mathematical constant, approximately equal to 2.71828). The wavenumber represents the (m, n)th acoustic mode (+ indicates the incident direction, - indicates the reflection direction along the axis), and i represents the imaginary unit. Represents the eigenfunctions, A represents the normalization parameter. For the normal absorption coefficient and plane wave transmission loss measured inside the impedance tube, it only depends on the sound pressure transfer function of each acoustic mode to the reference microphone, so A=1 is taken. It is a Bessel function of the first kind of order m.

[0045] The sound waves inside a pipe are not simple plane waves, but a complex sound field containing multiple circumferential (m-order) and radial (n-order) modes. Traditional methods that directly measure the average sound pressure level ignore modal differences, leading to inaccurate results. The core function of sound field modeling is to accurately describe the sound pressure composition at any point inside the pipe using mathematical formulas, decomposing the sound pressure at any point inside the pipe into "the sound pressure of each order of incident wave". "and "sound pressure of each order of reflected waves" It refers to the superposition of sounds, rather than the overall total sound pressure.

[0046] S102. Conduct 2M sound pressure tests, each test providing different pipe sound source characteristics or end boundary conditions. During each test, measure the sound pressure from multiple microphones arranged in the upstream pipe 3 and downstream pipe 4 of the pipe under test 2, and also obtain the sound pressure outside the pipe under test. .

[0047] Where M is the order of the acoustic mode. For example... Figure 4 As shown, during the sound pressure test, the sound source 5 is placed at the head end of the upstream pipe 3. G microphones are arranged in the upstream pipe 3 and the downstream pipe 4 respectively, with the G microphones arranged along the circumference and axial direction of the corresponding pipes. Since the sound mode decomposition requires accurate knowledge of the microphone positions inside the pipe, in order not to disrupt the sound field inside the pipe and to ensure easy positioning, the microphones are embedded in the inner wall of the pipe, with their measuring surfaces flush with the inner wall of the pipe.

[0048] The upstream and downstream pipes have thick walls and good sound insulation, with no sound leakage. However, the middle pipe to be tested (such as many corrugated pipes in engineering or pipes in automotive audio equipment) has poor sound insulation, so its sound insulation needs to be measured.

[0049] In real-world scenarios, the end boundary conditions cannot be easily altered (unless significantly different sound-absorbing materials are used at the downstream pipe end each time). Therefore, in this embodiment, each sound pressure test provides different pipe sound source characteristics, which is robust to solving the equations.

[0050] Specifically, the sound source 5 for the sound pressure test uses a speaker array, which can generate a multimodal sound field and provide different pipe sound source characteristics for each sound pressure test through different speaker sound output combinations.

[0051] In this embodiment, the sound pressure outside the pipe under test is obtained by a free-field microphone installed in the anechoic chamber. .

[0052] S103. For the general case of using G microphones to separate a total of M acoustic modes, the following acoustic mode separation equation exists:

[0053] ,

[0054] The sound pressure level for each test was calculated based on the aforementioned acoustic mode separation equation. - Similarly, the transmitted wave and its reflected wave in the downstream pipeline are taken as the incident wave and reflected wave of the pipeline, and the sound pressure level for each test is calculated according to the above acoustic mode separation equation. - ,in, to This represents the sound pressure measured by the first to the Gth microphones in either the upstream or downstream pipe. Represents the sound pressure of the first-order incident wave. Represents the sound pressure of the Mth incident wave. Represents the sound pressure of the first-order reflected wave. Represents the sound pressure of the Mth order reflected wave. The eigenfunction matrix represents the acoustic modes.

[0055] like Figure 4 The sound wave emitted by the sound source 5, i.e., the incident wave, propagates along the upstream pipe 3 towards the pipe under test 2. Because the acoustic impedance of the pipe under test 2 differs from that of the upstream pipe 3, according to the principle of impedance matching in acoustics, when a sound wave is incident from a medium with one acoustic impedance (upstream pipe 3) to the interface of a medium with another acoustic impedance (the pipe under test 2), not all energy can be "completely transmitted." A portion of the energy is reflected back to the original medium (upstream pipe 3). This reflected sound wave is the reflected wave. After being generated, the reflected wave propagates in the opposite direction along the upstream pipe 3 (opposite to the direction of the incident wave), eventually superimposing with the incident wave within the upstream pipe 3 to form a "mixed sound pressure signal" collected by the microphones within the upstream pipe. Therefore, the sound pressure obtained from the G microphones within the upstream pipe 3 can be measured. to Substituting into the acoustic mode separation equation, we obtain - The sound wave passing through the test pipe 2, i.e., the transmitted wave, propagates along the downstream pipe 4 towards the end. After encountering the end device 6, the reflected sound wave is the reflected wave of the transmitted wave. Therefore, the transmitted wave and the reflected wave can be regarded as the incident wave and the reflected wave in the downstream pipe 4. Thus, the measured sound pressure obtained from the G microphones in the downstream pipe 4 is substituted into the sound mode separation equation to obtain... - .

[0056] Specifically, when solving the above acoustic mode separation equation, an acoustic mode solving algorithm is used. This algorithm corresponds to the microphone arrangement. Several schemes are shown below:

[0057] 1. The microphones are evenly distributed circumferentially but have different axial spacing. Accordingly, the radial acoustic mode is solved using the spatial Fourier algorithm, and the axial acoustic mode is solved using the least squares method.

[0058] 2. The microphones are distributed in multiple interleaved Archimedean spirals, and correspondingly, the acoustic mode solving algorithm adopts the l2 regularization algorithm;

[0059] 3. The microphones are completely randomly distributed. Accordingly, the acoustic mode solving algorithm adopts Bayesian estimation plus l0 regularization algorithm.

[0060] 4. The microphones are basically randomly distributed, but the eigenfunction equations must be full rank. Accordingly, the least squares method is used to solve the acoustic modes.

[0061] S104, based on the sound pressure of 2M units , - , - The following acoustic mode expansion equations are used to calculate the results. :

[0062] .

[0063] The sound outside the pipe under test originates from the incident wave and the reflected wave of the transmitted wave, hence the equation:

[0064] ,

[0065] The above-mentioned acoustic mode expansion equation can be obtained by performing acoustic mode expansion on this equation.

[0066] in, The coefficients representing the incident waves of each order. The coefficients representing the reflected sound of each order of transmitted wave. Represents the incident sound pressure. The reflected sound pressure represents the transmitted wave.

[0067] S105, based on the calculation The sound insulation of the pipe wall under each acoustic mode is calculated using the following equation. :

[0068] .

[0069] in, This represents the incident sound power level of a certain acoustic mode. This represents the external sound power level of the corresponding acoustic mode outside the pipe wall under test.

[0070] As can be seen from step S104, the solution obtained by solving 2M equations... It is a fixed value and is not affected by the characteristics of the sound source or the boundary conditions at the end, thus... Calculated sound insulation It will not be affected by the characteristics of the sound source or the boundary conditions at the end.

[0071] As can be seen from the above, the method for measuring the sound insulation of a pipe wall provided in this application separates the incident wave sound pressure and reflected wave sound pressure in the pipe based on mathematical modeling, and further decomposes them into various sound modes. By providing different sound source characteristics or end boundary conditions in the pipe, the coefficients of each incident wave are solved, and the sound insulation of each sound mode is obtained based on the coefficients of each incident wave. This method can eliminate the interference of sound source characteristics and end boundary conditions in the pipe, and realize the accurate measurement of the inherent sound insulation properties of the pipe wall. It is suitable for complex sound field environments (such as pipe systems dominated by higher-order modes) and can provide the industry with a reliable sound insulation performance evaluation standard.

[0072] The following will describe in detail one or more embodiments of a pipe wall sound insulation measuring device according to the present invention. Those skilled in the art will understand that these devices can be configured using commercially available hardware components through the steps taught in this solution. Figure 2 This invention illustrates a device for measuring the sound insulation of a pipe wall, comprising a first module 11, a second module 12, a third module 13, a fourth module 14, and a fifth module 15.

[0073] Module 11, used in S101, models the sound field inside the pipe: Sound waves propagate in the impedance pipe, and the sound pressure satisfies the Helmholtz equation and rigid boundary conditions. The wall equation is independent of the propagation direction z. For the sound pressure at any point inside the circular pipe, considering the incident and reflected waves, the following is obtained using Bessel functions in cylindrical coordinates:

[0074] ,

[0075] in, Represents the coordinates of the pipeline. sound pressure, These represent the length, angle, and axial distance of the point along the circumferential radius, respectively. This represents the (m,n) order sound pressure along the axial incident direction. This represents the (m,n) order sound pressure along the axial reflection direction. It is the base of the natural logarithm (a mathematical constant, approximately equal to 2.71828). The wavenumber represents the (m, n)th acoustic mode (+ indicates the incident direction, - indicates the reflection direction along the axis), and i represents the imaginary unit. Represents the eigenfunctions, A represents the normalization parameter. For the normal absorption coefficient and plane wave transmission loss measured inside the impedance tube, it only depends on the sound pressure transfer function of each acoustic mode to the reference microphone, so A=1 is taken. It is a Bessel function of the first kind of order m.

[0076] The sound waves inside a pipe are not simple plane waves, but a complex sound field containing multiple circumferential (m-order) and radial (n-order) modes. Traditional methods that directly measure the average sound pressure level ignore modal differences, leading to inaccurate results. The core function of sound field modeling is to accurately describe the sound pressure composition at any point inside the pipe using mathematical formulas, decomposing the sound pressure at any point inside the pipe into "the sound pressure of each order of incident wave". "and "sound pressure of each order of reflected waves" It refers to the superposition of sounds, rather than the overall total sound pressure.

[0077] The second module 12 is used for S102 to perform 2M sound pressure tests. Each sound pressure test provides different pipe sound source characteristics or end boundary conditions. During each sound pressure test, the measured sound pressure is obtained from multiple microphones arranged in the upstream pipe 3 and downstream pipe 4 of the pipe under test 2, and the sound pressure outside the pipe under test is also obtained. .

[0078] Where M is the order of the acoustic mode. For example... Figure 4 As shown, during the sound pressure test, the sound source 5 is placed at the head end of the upstream pipe 3. G microphones are arranged in the upstream pipe 3 and the downstream pipe 4 respectively, with the G microphones arranged along the circumference and axial direction of the corresponding pipes. Since the sound mode decomposition requires accurate knowledge of the microphone positions inside the pipe, in order not to disrupt the sound field inside the pipe and to ensure easy positioning, the microphones are embedded in the inner wall of the pipe, with their measuring surfaces flush with the inner wall of the pipe.

[0079] The upstream and downstream pipes have thick walls and good sound insulation, with no sound leakage. However, the middle pipe to be tested (such as many corrugated pipes in engineering or pipes in automotive audio equipment) has poor sound insulation, so its sound insulation needs to be measured.

[0080] In real-world scenarios, the end boundary conditions cannot be easily altered (unless significantly different sound-absorbing materials are used at the downstream pipe end each time). Therefore, in this embodiment, each sound pressure test provides different pipe sound source characteristics, which is robust to solving the equations.

[0081] Specifically, the sound source 5 for the sound pressure test uses a speaker array, which can generate a multimodal sound field and provide different pipe sound source characteristics for each sound pressure test through different speaker sound output combinations.

[0082] In this embodiment, the sound pressure outside the pipe under test is obtained by a free-field microphone installed in the anechoic chamber. .

[0083] Module 13, used in S103, provides the following acoustic mode separation equation for the general case of using G microphones to separate a total of M acoustic modes:

[0084] ,

[0085] The sound pressure level for each test was calculated based on the aforementioned acoustic mode separation equation. - Similarly, the transmitted wave and its reflected wave in the downstream pipeline are taken as the incident wave and reflected wave of the pipeline, and the sound pressure level for each test is calculated according to the above acoustic mode separation equation. - ,in, to This represents the sound pressure measured by the first to the Gth microphones in either the upstream or downstream pipe. Represents the sound pressure of the first-order incident wave. Represents the sound pressure of the Mth incident wave. Represents the sound pressure of the first-order reflected wave. Represents the sound pressure of the Mth order reflected wave. The eigenfunction matrix represents the acoustic modes.

[0086] like Figure 4 The sound wave emitted by the sound source 5, i.e., the incident wave, propagates along the upstream pipe 3 towards the pipe under test 2. Because the acoustic impedance of the pipe under test 2 differs from that of the upstream pipe 3, according to the principle of impedance matching in acoustics, when a sound wave is incident from a medium with one acoustic impedance (upstream pipe 3) to the interface of a medium with another acoustic impedance (the pipe under test 2), not all energy can be "completely transmitted." A portion of the energy is reflected back to the original medium (upstream pipe 3). This reflected sound wave is the reflected wave. After being generated, the reflected wave propagates in the opposite direction along the upstream pipe 3 (opposite to the direction of the incident wave), eventually superimposing with the incident wave within the upstream pipe 3 to form a "mixed sound pressure signal" collected by the microphones within the upstream pipe. Therefore, the sound pressure obtained from the G microphones within the upstream pipe 3 can be measured. to Substituting into the acoustic mode separation equation, we obtain - The sound wave passing through the test pipe 2, i.e., the transmitted wave, propagates along the downstream pipe 4 towards the end. After encountering the end device 6, the reflected sound wave is the reflected wave of the transmitted wave. Therefore, the transmitted wave and the reflected wave can be regarded as the incident wave and the reflected wave in the downstream pipe 4. Thus, the measured sound pressure obtained from the G microphones in the downstream pipe 4 is substituted into the sound mode separation equation to obtain... - .

[0087] Specifically, when solving the above acoustic mode separation equation, an acoustic mode solving algorithm is used. This algorithm corresponds to the microphone arrangement. Several schemes are shown below:

[0088] 1. The microphones are evenly distributed circumferentially but have different axial spacing. Accordingly, the radial acoustic mode is solved using the spatial Fourier algorithm, and the axial acoustic mode is solved using the least squares method.

[0089] 2. The microphones are distributed in multiple interleaved Archimedean spirals, and correspondingly, the acoustic mode solving algorithm adopts the l2 regularization algorithm;

[0090] 3. The microphones are completely randomly distributed. Accordingly, the acoustic mode solving algorithm adopts Bayesian estimation plus l0 regularization algorithm.

[0091] 4. The microphones are basically randomly distributed, but the eigenfunction equations must be full rank. Accordingly, the least squares method is used to solve the acoustic modes.

[0092] Module 14, for S104, based on 2M sound pressure levels. , - , - The following acoustic mode expansion equations are used to calculate the results. :

[0093] .

[0094] The sound outside the pipe under test originates from the incident wave and the reflected wave of the transmitted wave, hence the equation:

[0095] ,

[0096] The above-mentioned acoustic mode expansion equation can be obtained by performing acoustic mode expansion on this equation.

[0097] in, The coefficients representing the incident waves of each order. The coefficients representing the reflected sound of each order of transmitted wave. Represents the incident sound pressure. The reflected sound pressure represents the transmitted wave.

[0098] Module 5, 15, is used for S105, based on the calculations. The sound insulation of the pipe wall under each acoustic mode is calculated using the following equation. :

[0099] .

[0100] in, This represents the incident sound power level of a certain acoustic mode. This represents the external sound power level of the corresponding acoustic mode outside the pipe wall under test.

[0101] As can be seen from step S104, the solution obtained by solving 2M equations... It is a fixed value and is not affected by the characteristics of the sound source or the boundary conditions at the end, thus... Calculated sound insulation It will not be affected by the characteristics of the sound source or the boundary conditions at the end.

[0102] In summary, the pipe wall sound insulation measurement device provided in the above embodiments can perform the pipe wall sound insulation measurement method provided in the foregoing embodiments.

[0103] Similar to the above concept, the above Figure 2 The structure of the pipe wall sound insulation measuring device shown can be implemented as an electronic device. Figure 3 A schematic block diagram of the structure of an electronic device provided by an embodiment of the present invention is shown.

[0104] For example, the electronic device includes a storage module 21 and a processor 22. The storage module 21 includes instructions loaded and executed by the processor 22, which, when executed, cause the processor 22 to perform the steps described in the section on a method for measuring the sound insulation of a pipe wall described above, according to various exemplary embodiments of the present invention.

[0105] It should be understood that processor 22 can be a Central Processing Unit (CPU), or it can be other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. Among these, the general-purpose processor can be a microprocessor or any conventional processor.

[0106] This invention also provides a computer-readable storage medium that stores one or more programs, which, when executed by a processor, implement the steps described in the section on measuring the sound insulation of a pipe wall according to various exemplary embodiments of the invention.

[0107] Those skilled in the art will understand that all or some of the steps, systems, and apparatuses disclosed above, and their functional modules / units, can be implemented as software, firmware, hardware, or suitable combinations thereof. In hardware implementations, the division between functional modules / units mentioned above does not necessarily correspond to the division of physical components; for example, a physical component may have multiple functions, or a function or step may be performed collaboratively by several physical components. Some or all physical components may be implemented as software executed by a processor, such as a central processing unit, digital signal processor, or microprocessor, or as hardware, or as an integrated circuit, such as an application-specific integrated circuit (ASIC). Such software can be distributed on a computer-readable storage medium, which may include computer-readable storage media (or non-transitory media) and communication media (or transient media).

[0108] As is known to those skilled in the art, the term computer-readable storage medium includes volatile and non-volatile, removable and non-removable media implemented in any method or technology for storing information (such as computer-readable instructions, data structures, program modules, or other data). Computer-readable storage media includes, but is not limited to, RAM, ROM, EEPROM, flash memory or other memory technologies, CD-ROM, digital versatile disc (DVD) or other optical disc storage, magnetic cartridges, magnetic tape, disk storage or other magnetic storage devices, or any other medium that can be used to store desired information and is accessible to a computer. Furthermore, it is known to those skilled in the art that communication media typically contain computer-readable instructions, data structures, program modules, or other data in modulated data signals such as carrier waves or other transmission mechanisms, and may include any information delivery medium.

[0109] For example, the computer-readable storage medium may be an internal storage unit of the electronic device described in the foregoing embodiments, such as a hard disk or memory of the electronic device. The computer-readable storage medium may also be an external storage device of the electronic device, such as a plug-in hard disk, Smart Media Card (SMC), Secure Digital (SD) card, Flash Card, etc., provided on the electronic device.

[0110] The electronic devices and computer-readable storage media provided in the foregoing embodiments separate the incident wave sound pressure and reflected wave sound pressure in the pipeline based on mathematical modeling, and further decompose them into various sound modes. By providing different sound source characteristics or end boundary conditions in the pipeline, the coefficients of each incident wave are solved, and the sound insulation of each sound mode is obtained based on the coefficients of each incident wave. This can eliminate the interference of sound source characteristics and end boundary conditions in the pipeline, realize the accurate measurement of the inherent sound insulation properties of the pipe wall, and is suitable for complex sound field environments (such as pipeline systems dominated by higher-order modes). It can provide the industry with a reliable sound insulation performance evaluation standard.

[0111] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the scope of this application. Therefore, if such modifications and variations fall within the scope of the claims of this application and their equivalents, this application also intends to include such modifications and variations.

Claims

1. A method for measuring the sound insulation of a pipe wall, characterized in that, include: Modeling the sound field inside the pipe: For the sound pressure at any point inside the circular pipe, considering the incident and reflected waves, the expansion using Bessel functions in cylindrical coordinates is as follows: ， in, Represents the coordinates of the pipeline. sound pressure, These represent the length, angle, and axial distance of the point along the circumferential radius, respectively. This represents the (m,n) order sound pressure along the axial incident direction. This represents the (m,n) order sound pressure along the axial reflection direction. It is the base of the natural logarithm. The wave number represents the (m, n)th acoustic mode, and i represents the imaginary unit. Represents the eigenfunctions, A represents the normalization parameter, and we take A=1. It is a Bessel function of the first kind of order m; Two million sound pressure tests were conducted, each with different pipe sound source characteristics or end boundary conditions. During each test, the sound pressure was measured from multiple microphones arranged in the upstream and downstream pipes of the pipe under test, and the sound pressure outside the pipe under test was also acquired. Where M is the order of the acoustic mode, and G microphones are arranged in the upstream and downstream pipes respectively, with the G microphones arranged along the circumference and axial direction of the corresponding pipes. For the general case of using G microphones to separate a total of M acoustic modes, the following acoustic mode separation equations exist: ， The sound pressure level for each test was calculated based on the aforementioned acoustic mode separation equation. - Similarly, the transmitted wave and its reflected wave in the downstream pipeline are taken as the incident wave and reflected wave of the pipeline, and the sound pressure level for each test is calculated according to the aforementioned acoustic mode separation equation. - ,in, to This represents the sound pressure measured by the first to the Gth microphones in either the upstream or downstream pipe. Represents the sound pressure of the first-order incident wave. Represents the sound pressure of the Mth incident wave. Represents the sound pressure of the first-order reflected wave. Represents the sound pressure of the Mth order reflected wave. The eigenfunction matrix representing the acoustic modes; Based on the sound pressure of 2M , - , - And the following equation, calculated to obtain : ， in, The coefficients representing the incident waves of each order. The coefficients representing the reflected sound at each order of transmitted sound; Based on the calculation The sound insulation of the pipe wall under test in each acoustic mode is calculated using the following equation. : 。 2. The method for measuring the sound insulation of a pipe wall according to claim 1, characterized in that, Each sound pressure test provides different pipe sound source characteristics.

3. The method for measuring the sound insulation of a pipe wall according to claim 2, characterized in that, The sound source for the sound pressure test is a speaker array.

4. The method for measuring the sound insulation of a pipe wall according to claim 3, characterized in that, Different combinations of horn outputs provide different pipe sound source characteristics for each sound pressure test.

5. The method for measuring the sound insulation of a pipe wall according to claim 1, characterized in that, The microphone is embedded in the inner wall of the pipe, and its measuring surface is flush with the inner wall of the pipe.

6. The method for measuring the sound insulation of a pipe wall according to claim 1, characterized in that, The sound pressure outside the pipe under test is obtained by a free-field microphone installed in the anechoic chamber. .

7. A device for measuring the sound insulation of a pipe wall, characterized in that, include: The first module is used to model the sound field inside the pipe: For the sound pressure at any point inside the circular pipe, considering the incident wave and the reflected wave, the expansion using Bessel functions in cylindrical coordinates is as follows: ， in, Represents the coordinates of the pipeline. sound pressure, These represent the length, angle, and axial distance of the point along the circumferential radius, respectively. This represents the (m,n) order sound pressure along the axial incident direction. This represents the (m,n) order sound pressure along the axial reflection direction. It is the base of the natural logarithm. The wave number represents the (m, n)th acoustic mode, and i represents the imaginary unit. Represents the eigenfunctions, A represents the normalization parameter, and we take A=1. It is a Bessel function of the first kind of order m; The second module is used to perform 2M sound pressure tests. Each sound pressure test provides different pipe sound source characteristics or end boundary conditions. During each sound pressure test, the measured sound pressure is obtained from multiple microphones arranged in the upstream and downstream pipes of the pipe under test, and the sound pressure outside the pipe under test is also obtained. Where M is the order of the acoustic mode, and G microphones are arranged in the upstream and downstream pipes respectively, with the G microphones arranged along the circumference and axial direction of the corresponding pipes. The third module is used for the general case of separating a total of M acoustic modes using G microphones, with the following acoustic mode separation equation: ， The sound pressure level for each test was calculated based on the aforementioned acoustic mode separation equation. - Similarly, the transmitted wave and its reflected wave in the downstream pipeline are taken as the incident wave and reflected wave of the pipeline, and the sound pressure level for each test is calculated according to the aforementioned acoustic mode separation equation. - ,in, to This represents the sound pressure measured by the first to the Gth microphones in either the upstream or downstream pipe. Represents the sound pressure of the first-order incident wave. Represents the sound pressure of the Mth incident wave. Represents the sound pressure of the first-order reflected wave. Represents the sound pressure of the Mth order reflected wave. The eigenfunction matrix representing the acoustic modes; The fourth module is used to calculate the sound pressure levels of 2M units. , - , - Calculate using the following equation: : ， in, The coefficients representing the incident waves of each order. The coefficients representing the reflected sound at each order of transmitted sound; The fifth module is used to calculate... The sound insulation of the pipe wall under test in each acoustic mode is calculated using the following equation. : 。 8. An electronic device, characterized in that, The device includes a storage module containing instructions loaded and executed by a processor, which, when executed, cause the processor to perform a method for measuring the sound insulation of a pipe wall according to any one of claims 1-6.

9. A computer-readable storage medium storing one or more programs, characterized in that, When the one or more programs are executed by the processor, they implement the method for measuring the sound insulation of a pipe wall as described in any one of claims 1-6.

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