Ultrasonic gas flowmeter and method for adjusting the angle of its acoustic field

Abstract

The application provides an ultrasonic gas flowmeter and an acoustic field angle adjusting method thereof. The ultrasonic gas flowmeter comprises a sensor structure and an acoustic structure, and the sensor structure and / or the acoustic structure are in an adjustable configuration. According to different pipeline structures and installation conditions, at least one design parameter of the sensor structure and / or the acoustic structure is adjusted to change the acoustic field angle finally output by the ultrasonic gas flowmeter. In the embodiment of the application, the sensor structure and the acoustic structure are designed as an adjustable configuration, so that the flowmeter can actively adapt to diversified pipeline structures and installation conditions, and can be particularly applicable to pipeline designs with very narrow widths. The ultrasonic gas flowmeter provided by the application can reduce the overall size of the sensor while obtaining greater signal strength.

Description

Technical Field

[0001] This application relates to the field of electronic circuit technology, and more specifically, to an ultrasonic gas flow meter and a method for adjusting the sound field angle thereon. Background Technology

[0002] An ultrasonic gas flow meter is an instrument that measures flow velocity and flow rate by utilizing the time difference between the propagation of ultrasonic waves in a fluid with and against the flow. Due to its advantages such as non-contact operation, no pressure loss, and wide rangeability, it has been widely used in industrial metering, energy management and other fields.

[0003] Traditional ultrasonic gas flow meters generally use block sensors made of piezoelectric ceramic materials as the sound wave transmitting and receiving units. These sensors typically operate based on thickness vibration modes, and their acoustic characteristics (especially the sound field angle, i.e., the angular range in which sound wave energy is mainly concentrated) are determined by the sensor's own physical properties at the factory. Specifically, the sensor's sound field angle mainly depends on the geometric dimensions of its elements (such as the diameter-to-thickness ratio) and the material properties of the piezoelectric ceramic. The large size of block sensors made of piezoelectric ceramic materials severely limits the freedom of pipeline design, making it difficult for flow meters to flexibly adapt to diverse installation scenarios and application requirements. Summary of the Invention

[0004] The purpose of this application is to provide an ultrasonic gas flow meter that can flexibly adjust the size of the sound field angle to adapt to different pipeline designs.

[0005] An ultrasonic gas flow meter with adjustable sound field angle includes: a sensor structure and an acoustic structure, wherein the sensor structure includes one or more thin-film sensors;

[0006] The acoustic structure includes an acoustic horn for beamforming the sound waves emitted or received by the thin-film sensor.

[0007] The sensor structure and / or the acoustic structure are adjustable. Depending on different pipe structures and installation conditions, at least one design parameter of the sensor structure and / or the acoustic structure can be adjusted to change the final output sound field angle of the ultrasonic gas flow meter.

[0008] In one embodiment, the design parameters of the sensor structure include: the number of thin-film sensors and the spacing between the thin-film sensors.

[0009] In one embodiment, the acoustic horn includes: an inlet end, an outlet end, and a transition section connecting the inlet end and the outlet end, wherein the sensor structure is disposed at the inlet end, and the outlet end faces the pipe structure;

[0010] The design parameters of the acoustic structure include: the size of the inlet end, the size of the outlet end, and the shape or variation trend of the transition section.

[0011] In one embodiment, the sensor structure includes a sensor array; the sensor array is a thin-film sensor with a multi-diaphragm structure, and / or multiple thin-film sensors with a single-diaphragm structure;

[0012] The projection profile of the outlet end of the acoustic loudspeaker in the XY plane has a first distance in the X direction and a second distance in the Y direction.

[0013] The magnitude of the sound field angle ultimately output by the ultrasonic gas flow meter is related to (a) the symmetry of the sensor array arrangement in the XY plane; and (b) the ratio between the first distance and the second distance.

[0014] In one embodiment, the sensor array is symmetrically arranged in the XY plane, and the first distance is equal to the second distance, so that the final output sound field is an isotropic sound field.

[0015] In one embodiment, the sensor array is asymmetrically arranged in the XY plane, the first distance and the second distance are not equal, and their design parameters are configured to compensate for each other, so that the final output sound field is symmetrical in the XZ plane and the YZ plane, and the final output sound field is an isotropic sound field.

[0016] In one embodiment, the sensor array is symmetrically arranged in the XY plane, and the first distance and the second distance are not equal, so that the sound field angles in the X direction and the Y direction of the final output sound field are different, making the final output sound field anisotropic.

[0017] In one embodiment, the sensor array is asymmetrically arranged in the XY plane, and the first distance and the second distance at the outlet of the acoustic horn are not equal. The design parameters of both are configured such that the final output sound field is asymmetrical in the XZ plane and the YZ plane, making the final output sound field anisotropic.

[0018] In one embodiment, the ratio of the first distance to the second distance can be adjusted according to the design requirements of the output sound field when the acoustic structure is applied to different sound field environments.

[0019] In one embodiment, the sensor array has a symmetrical arrangement in the XY plane, including:

[0020] The sensor structure includes a thin-film sensor located at the center of the inlet end;

[0021] or,

[0022] The sensor structure includes multiple thin-film sensors arranged in an array, with the array of thin-film sensors located at the center of the inlet end; in the XY plane, the distance between the multiple thin-film sensors in the X direction is a, and the distance between the multiple thin-film sensors in the Y direction is b, and a=b.

[0023] In one embodiment, the sensor array has an asymmetric arrangement in the XY plane, including:

[0024] The sensor structure includes multiple thin-film sensors arranged in an array, with the array of thin-film sensors located at the center of the inlet end; in the XY plane, the distance between the multiple thin-film sensors in the X direction is a, and the distance between the multiple thin-film sensors in the Y direction is b, and a≠b.

[0025] In one embodiment, the thin-film sensor is a piezoelectric MEMS thin-film sensor or a flexible piezoelectric thin-film sensor.

[0026] In one embodiment, when the thin-film sensors are arranged in an array, the sound field angle can be electronically adjusted by controlling the excitation mode of the array in conjunction with the acoustic horn.

[0027] In one embodiment, the sensor structure and the acoustic structure are integrated and packaged into a single transducer unit that can be installed as a whole.

[0028] A method for adjusting the sound field angle of an ultrasonic gas flow meter according to any one of the above-mentioned methods, comprising the steps of:

[0029] Determine the required target sound field angle based on the acoustic path design requirements of the target pipeline;

[0030] By adjusting at least one design parameter of the acoustic structure and / or the sensor structure, the final output sound field angle of the ultrasonic gas flow meter is changed to adapt to the acoustic path design requirements of the target pipeline.

[0031] In one embodiment, the method further includes: optimizing the acoustic field characteristics by adjusting the operating parameters or excitation mode of the thin-film sensor.

[0032] This application has at least the following advantages or beneficial effects:

[0033] 1. In this application embodiment, by designing the sensor structure and acoustic structure as adjustable, a core means for adjusting the final output sound field angle is provided, breaking through the limitations of traditional fixed sound field angle sensors. This allows the flow meter to actively adapt to diverse pipe structures and installation conditions, fundamentally solving the problem of gain reduction and measurement performance degradation caused by acoustic mismatch. The ultrasonic gas flow meter provided in this application has an adjustable sound field angle, making it suitable for pipe designs with very narrow widths. When the ultrasonic gas flow meter with an adjustable sound field angle is applied to a pipe design with very narrow widths, if the directivity in one direction is too high, it will cause reflection. Therefore, by adjusting at least one design parameter in the sensor structure and / or acoustic structure, the sound field angle in this direction can be reduced so that the final output sound field angle meets the user's requirements. The ultrasonic gas flow meter provided in this application achieves a larger signal strength while reducing the overall sensor size.

[0034] 2. In this embodiment, the adjustable sound field angle of the ultrasonic gas flow meter is flexibly controlled by (a) the symmetry of the sensor array arrangement in the XY plane and (b) the coordinated control of the ratio between the first distance L1 and the second distance L2. If the outlet end of the acoustic horn is circular, the ratio of the first distance L1 to the second distance L2 is 1:1; if the outlet end of the acoustic horn is elliptical, the ratio of the first distance L1 to the second distance L2 is not equal to 1:1. The ratio of the first distance L1 to the second distance L2 determines the difference in the diameter of the outlet end of the acoustic horn in the X and Y directions, which is a structural parameter for controlling the anisotropy of the beam divergence angle. In this embodiment, two core coordinated design elements that determine the final sound field angle characteristics (sensor arrangement symmetry and outlet end profile length ratio) are revealed. By purposefully combining these two elements (such as symmetrical arrangement with non-equal length outlets, or asymmetrical arrangement with equal length outlets), users / product design engineers can accurately predict and control the anisotropy (symmetry) and angle of the output sound field, achieving a leap from uncontrollable to programmable design of sound field performance.

[0035] (1) In this embodiment, the sensor array is symmetrically arranged and the acoustic horn has an equal-length outlet. This configuration ensures that the sound waves propagate in all directions with the same divergence angle in the pipe, which is suitable for classic installation scenarios such as through-beam type that require uniform sound field coverage, and achieves the best symmetrical coupling and signal stability.

[0036] (2) In the embodiments of this application, the configuration of asymmetric arrangement of sensor array + non-equal length outlet of acoustic horn (compensation type) is defined. When the sensor array is asymmetric due to process or layout limitations, the directivity of the sensor itself can be offset by designing an outlet of acoustic horn with a specific aspect ratio (for example, using a longer outlet size in the direction of larger sensor spacing), and finally outputting a symmetrical sound field, thereby improving design tolerance and final performance.

[0037] (3) In the embodiments of this application, a configuration of symmetrical sensor array and non-uniform length acoustic horn outlet is specified. By using the symmetrical sensors and non-circular outlets such as elliptical or rectangular ones, sound fields with different divergence angles in the X and Y directions can be generated in a low-cost and efficient manner. This is particularly suitable for special pipe geometries that require sound waves to be more concentrated in one direction (such as narrow channels) and wider in another direction (such as wide pipes).

[0038] (4) In this embodiment, a configuration of asymmetric sensor array arrangement + non-uniform length acoustic horn outlet (superimposed type) is defined. This provides maximum design flexibility and functional expandability. By superimposing sensor asymmetry and horn outlet asymmetry, more complex and extreme sound field shaping can be achieved, such as generating highly focused elliptical sound spots or fan-shaped sound fields with specific deflection angles, to meet the demanding requirements of complex acoustic layouts such as reflective and multipath systems.

[0039] 3. The ultrasonic gas flow meter described in this application embodiment can be applied to classic installation scenarios requiring uniform sound field coverage, such as through-beam flow meters, achieving optimal symmetrical coupling and signal stability. The ultrasonic gas flow meter described in this application embodiment can also be applied to reflective ultrasonic gas flow meters, or "V"-shaped ultrasonic gas flow meters, or "Z"-shaped ultrasonic gas flow meters. Attached Figure Description

[0040] To more clearly illustrate the technical solutions in the specific embodiments of this application or the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0041] Figure 1 A schematic diagram showing the configuration relationship between the sensor structure and the acoustic structure, and the output sound field in the ultrasonic gas flow meter with adjustable sound field angle provided in the first embodiment of this application;

[0042] Figure 2A schematic diagram of the configuration relationship between the sensor structure and the acoustic structure and the output sound field in the ultrasonic gas flow meter with adjustable sound field angle provided in the second embodiment of this application;

[0043] Figure 3 A schematic diagram of the configuration relationship between the sensor structure and the acoustic structure and the output sound field in the ultrasonic gas flow meter with adjustable sound field angle provided in the third embodiment of this application;

[0044] Figure 4 A schematic diagram of the configuration relationship between the sensor structure and the acoustic structure and the output sound field in the ultrasonic gas flow meter with adjustable sound field angle provided in the fourth embodiment of this application;

[0045] Figure 5 A schematic diagram of the configuration relationship between the sensor structure and the acoustic structure and the output sound field in the ultrasonic gas flow meter with adjustable sound field angle provided in the fifth embodiment of this application;

[0046] Figure 6 A schematic diagram of the configuration relationship between the sensor structure and the acoustic structure and the output sound field in the ultrasonic gas flow meter with adjustable sound field angle provided in the sixth embodiment of this application;

[0047] Figure 7a A schematic diagram of the acoustic structure of an ultrasonic gas flow meter with adjustable sound field angle provided in one embodiment of this application;

[0048] Figure 7b for Figure 7a The schematic diagram of the ultrasonic gas flow meter with adjustable sound field angle provided in the XZ plane;

[0049] Figure 7c for Figure 7a The diagram shows the structure of the ultrasonic gas flow meter with adjustable sound field angle in the YZ plane.

[0050] Figure 8a This is a schematic diagram of the sound field angle in the XZ plane for an ultrasonic gas flow meter that does not have an acoustic structure or where the sensor structure and acoustic structure are not adjusted and configured in the prior art.

[0051] Figure 8b This is a schematic diagram of the sound field angle in the YZ plane for an ultrasonic gas flow meter that does not have an acoustic structure or where the sensor structure and acoustic structure are not adjusted and configured in the prior art.

[0052] Figure 9a For this application Figures 7a-7c The diagram shows the sound field angle of an ultrasonic gas flow meter with adjustable sound field angle in the XZ plane.

[0053] Figure 9b For this application Figures 7a-7c The diagram shows the sound field angle of an ultrasonic gas flow meter with adjustable sound field angle in the YZ plane.

[0054] Figure 10 A schematic diagram of the structure of an ultrasonic gas flow meter with adjustable sound field angle provided in one embodiment of this application, applied to a reflective ultrasonic gas flow meter;

[0055] Figure 11 This is a schematic diagram of the structure of an ultrasonic gas flow meter with adjustable sound field angle provided in one embodiment of the present application, applied to a through-beam ultrasonic gas flow meter.

[0056] Explanation of reference numerals in the attached figures:

[0057] Ultrasonic gas flow meter 100:

[0058] Sensor structure 10;

[0059] Acoustic structure 20: inlet end 21, outlet end 22, transition section 23;

[0060] Test body 30: First connector 31, second connector 32;

[0061] Test pipe 40;

[0062] Fluid-stabilized structure 20a;

[0063] Rectifier 50: rectifier body 51, rectifier channel 52;

[0064] Sound field 200. Detailed Implementation

[0065] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0066] Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0067] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0068] In the description of this application, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of the invention is in use. They are used only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application. In addition, the terms "first," "second," and "third," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0069] Furthermore, terms such as "horizontal" and "vertical" do not imply that components must be absolutely horizontal or suspended, but rather that they can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal than "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0070] In the description of this application, it should also be noted that, unless otherwise expressly specified and limited, the terms "set up," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0071] Please see Figures 1-6 , Figure 10 and Figure 11 This application provides an ultrasonic gas flow meter 100, the ultrasonic gas flow meter 100 having an adjustable sound field angle. The ultrasonic gas flow meter 100 includes a sensor structure 10 and an acoustic structure 20. The sensor structure 10 includes one or more thin-film sensors. The acoustic structure 20 includes an acoustic horn for beamforming the sound waves emitted or received by the thin-film sensors. The sensor structure 10 can be configured as a miniature thin-film sensor chip. The sensor structure 10 can be a single element (i.e., a single thin-film sensor) or an array of elements (i.e., multiple thin-film sensors), with the element array having a stronger ability to converge the sound field. When the sensor structure 10 includes multiple thin-film sensors (thin-film sensor array), the spacing d of the thin-film sensor array satisfies d < 3 * wavelength. The wavelength is determined by the resonant frequency of the thin-film sensor, wavelength = sound speed / resonant frequency.

[0072] Figures 1-6The diagrams show the configuration relationship between the sensor structure 10 and the acoustic structure 20 in the ultrasonic gas flow meter 100 and the output sound field in six different embodiments.

[0073] Figure 7a This is a schematic diagram of the acoustic structure of an ultrasonic gas flow meter with adjustable sound field angle provided in one embodiment of this application. Figure 7a As shown, the acoustic structure 20 includes an inlet end 21, an outlet end 22, and a transition section 23. The acoustic structure 20 can be integrally formed or fabricated separately and then assembled. The inlet end 21 and the outlet end 22 are the acoustic inlet and outlet of the acoustic loudspeaker, respectively. The transition section 23 is the connector that connects the inlet end 21 and the outlet end 22. The inlet end 21 and the outlet end 22 have cross-sections in the XY plane, and the diameter of these cross-sections is variable / adjustable. The transition section 23 has multiple cross-sections in the XY plane; the shape of these cross-sections is not limited and can be circular, elliptical, rectangular, rhomboid, polygonal, or other shapes. The shape of the cross-sections of the inlet end 21 and the outlet end 22 is also not limited and can be circular, elliptical, rectangular, rhomboid, polygonal, or other shapes. The shape types of the cross-sections of the inlet end 21 and the outlet end 22 can be the same or different.

[0074] The sensor structure 10 and / or acoustic structure 20 are adjustable, and the sound field angle of the final output of the ultrasonic gas flow meter can be changed by adjusting at least one of its design parameters according to different pipeline structures and installation conditions.

[0075] In this embodiment, by designing the sensor structure 10 and the acoustic structure 20 as adjustable configurations, a core means of adjusting the final output sound field angle is provided, breaking through the limitations of traditional fixed sound field angle sensors. This enables the flow meter to actively adapt to diverse pipe structures and installation conditions, fundamentally solving the problem of gain reduction and measurement performance degradation caused by acoustic mismatch.

[0076] In this embodiment, the ultrasonic gas flow meter 100 is applicable to narrow pipe designs. When the ultrasonic gas flow meter 100 is applied to a narrow pipe design, if the directivity in one direction is too high, it will cause reflection. Therefore, the sound field angle in this direction can be reduced by adjusting at least one design parameter in the sensor structure 10 and / or the acoustic structure 20 so that the final output sound field angle meets the user's requirements.

[0077] In one embodiment, the design parameters of the sensor structure 10 include: the number of thin-film sensors and the spacing between the thin-film sensors. The number of thin-film sensors (any positive integer, adjustable as needed) can be set to 1, 2, 3, 4, 5, 6, 7, 8, 9... This list is not exhaustive. Various arrangements of the thin-film sensors can be attempted. In one embodiment, the array of thin-film sensors can be configured as a matrix of 2*2, 3*3, 4*4, 5*5, etc. The spacing between the thin-film sensors can be as follows... Figure 1 The spacing 'a' shown is also possible. The spacing between thin-film sensors can also be as follows: Figure 2 , Figure 3 , Figure 4 , Figure 5 The spacings a and b are shown. The spacing between thin-film sensors can also be as follows: Figure 6 The spacings shown are a1, a2, b1, and b2.

[0078] This embodiment clarifies the key design parameters (number and spacing) of the sensor structure 10. By changing the number or spacing of the sensors, the size and directivity of the synthesized sound source can be directly affected, providing a foundation for achieving a wide-angle coverage sound field distribution, or a highly directional sound field distribution.

[0079] In one embodiment, such as Figure 7a The acoustic structure 20 shown can be configured as an acoustic horn. The acoustic horn includes an inlet end 21, an outlet end 22, and a transition section 23 connecting the inlet end 21 and the outlet end 22. The sensor structure 10 is located at the inlet end 21, and the outlet end 22 faces the pipe structure. The acoustic horn is a hollow waveguide structure, with its internal cavity forming a sound wave channel that extends along the direction of sound wave propagation. The inlet end 21, also called the sensor coupling end or narrow end, has dimensions adapted to the effective radiation / receiving surface of the thin-film sensor for coupling acoustic energy. The outlet end 22, also called the acoustic window end or wide end, faces the measured fluid inside the pipe, through which sound waves exit or enter. The transition section 23 connects the cavity wall of the inlet end 21 and the outlet end 22, and its profile determines the transformation law of the sound waves. Figure 7aThe connecting line of the transition section 23 is a straight line; in other embodiments, the connecting line of the transition section 23 can also be a curve. The design parameters of the acoustic structure 20 include: the dimensions of the inlet end 21, the dimensions of the outlet end 22, and the shape or variation trend of the transition section 23. The dimensions of the inlet end 21 include its structure or shape, and its aperture or diameter (if the inlet end 21 is elliptical, the dimensions include the lengths of its major and minor axes). The dimensions of the outlet end 22 are also considered. The shape of the transition section 23 can be a stepped variable cross-section structure or a gradually changing curved variable cross-section structure (similar to a horn, vase, etc.). The variation trend of the transition section 23 includes exponential curve variation, hyperbolic variation, Bézier curve variation, and polynomial curve variation.

[0080] This embodiment clarifies the specific structure of the acoustic horn (inlet end 21, outlet end 22, transition section 23) and its key design parameters. The abstract acoustic structure 20 is concretized into designable and manufacturable physical features. By defining the dimensions of the inlet end 21, the outlet end 22, and the contour of the transition section 23, a precise engineering control method is provided for adjusting the shape of the sound wave beam (such as divergence, convergence, and deflection) through mechanical structures, which is the structural basis for achieving quantitative adjustment of the sound field angle.

[0081] In one embodiment, the sensor structure 10 includes a sensor array (such as a square array of 2*2, 3*3, 4*4, 5*5, etc.). Figure 7b and Figure 7c As shown, the projected profile of the outlet end 22 of the acoustic horn in the XY plane has a length of a first distance L1 in the X direction and a length of a second distance L2 in the Y direction. In some embodiments, the sensor array is a thin-film sensor with a multi-diaphragm structure; in some embodiments, the sensor array is a plurality of thin-film sensors with a single-diaphragm structure; in some embodiments, the sensor array is a combination of a thin-film sensor with a multi-diaphragm structure and a plurality of thin-film sensors with a single-diaphragm structure.

[0082] The magnitude of the final sound field angle output by the ultrasonic gas flow meter 100 is related to (a) the symmetry of the sensor array arrangement in the XY plane; and (b) the ratio between the first distance L1 and the second distance L2. That is, the final sound field characteristics, including the magnitude of the sound field angle and the symmetry relationship of the sound field angle in the XZ plane and the YZ plane, are jointly determined by (a) and (b).

[0083] In this embodiment, the final output sound field angle of the ultrasonic gas flow meter 100 is flexibly controlled by (a) the symmetry of the sensor array arrangement in the XY plane and (b) the coordinated control of the ratio between the first distance L1 and the second distance L2. If the outlet end 22 of the acoustic horn is circular, the ratio of the first distance L1 to the second distance L2 is 1:1; if the outlet end 22 of the acoustic horn is elliptical, the ratio of the first distance L1 to the second distance L2 is not equal to 1:1. The ratio of the first distance L1 to the second distance L2 determines the difference in the aperture of the outlet end 22 of the acoustic horn in the X and Y directions, and is a structural parameter for controlling the anisotropy of the beam divergence angle. In this embodiment, two core coordinated design elements that determine the final sound field angle characteristics (sensor arrangement symmetry and outlet end profile length ratio) are revealed. By purposefully combining these two elements (such as symmetrical arrangement with non-equal length outlets, or asymmetrical arrangement with equal length outlets), users / product design engineers can accurately predict and control the anisotropy (symmetry) and angle of the output sound field, achieving a leap from uncontrollable to programmable design of sound field performance.

[0084] In one embodiment, such as Figure 2 and Figure 6 As shown, the sensor array is symmetrically arranged in the XY plane, and the first distance L1 and the second distance L2 at the acoustic horn outlet are equal, making the output sound field is isotropic. Figure 2 The diagram shows a 2x2 square array with a square outlet. (Example:) Figure 6 The 3x3 square array shown is equipped with a circular outlet for an acoustic speaker.

[0085] In this embodiment, a symmetrical arrangement of the sensor array and an acoustic horn with an equal-length outlet are specified. This configuration ensures that sound waves propagate in all directions within the duct with the same divergence angle, making it suitable for classic installation scenarios such as through-beam systems that require uniform sound field coverage, and achieving optimal symmetrical coupling and signal stability.

[0086] In one embodiment, such as Figure 5 As shown, the sensor array is asymmetrically arranged in the XY plane, the first and second distances at the acoustic horn outlets are unequal, and their design parameters are configured to compensate for each other, making the output sound field symmetrical in the XZ and YZ planes. Figure 5 The diagram shows a 2x2 rectangular array with a rectangular outlet for the acoustic horn. The large sensor spacing in the Y-direction results in a narrow beam in that direction; therefore, an elliptical outlet with a longer Y-direction length is used to widen the Y-direction beam, ultimately making the beam widths in both directions consistent. For example, if the sensor array is designed as a rectangle, resulting in a larger sound field angle along the shorter rectangular side, an elliptical acoustic horn can be used, with the horn's convergence point corresponding to the shorter side.

[0087] In this embodiment, a configuration of asymmetrical sensor array arrangement and non-uniform length acoustic horn outlets (compensation type) is defined. When the sensor array is asymmetrical due to process or layout limitations, compensation can be achieved by designing the acoustic horn outlet with a specific aspect ratio (e.g., using a longer outlet size in the direction of larger sensor spacing). This can counteract the directivity of the sensors themselves, ultimately outputting a symmetrical sound field, improving design tolerance and final performance.

[0088] In one embodiment, such as Figure 4 As shown, the sensor array is symmetrically arranged in the XY plane with a=b, and the first distance L1 and the second distance L2 at the acoustic horn outlet are not equal, resulting in a difference in the sound field angle in the X direction and the sound field angle in the Y direction. A 2*2 square sensor array, paired with an acoustic horn with an elliptical outlet, actively generates anisotropic sound field angles.

[0089] In this embodiment, a symmetrical arrangement of the sensor array and a non-uniform length acoustic horn outlet are specified. By utilizing the inherently symmetrical sensors and combining them with non-circular outlets such as elliptical or rectangular ones, sound fields with different divergence angles in the X and Y directions can be generated cost-effectively and efficiently. This is particularly suitable for special pipe geometries that require sound waves to be more concentrated in one direction (such as narrow channels) and more diffuse in another direction (such as wide pipes).

[0090] In one embodiment, such as Figure 3 As shown, the sensor array has an asymmetrical arrangement in the XY plane, a≠b, and the first distance L1 and the second distance L2 at the outlet of the acoustic speaker are not equal. The design parameters of both are configured to make the output sound field asymmetrical in the XZ plane and the YZ plane.

[0091] In this embodiment, a configuration of asymmetrical sensor array arrangement and non-uniform length acoustic horn outlets (superimposed type) is defined. This provides maximum design flexibility and functional scalability. By superimposing sensor asymmetry and horn outlet asymmetry, more complex and extreme sound field shaping can be achieved, such as generating highly focused elliptical sound spots or fan-shaped sound fields with specific deflection angles, to meet the demanding requirements of complex acoustic layouts such as reflective and multipath acoustics.

[0092] In one embodiment, the ratio of the first distance L1 to the second distance L2 can be adjusted according to the design requirements of the output sound field when the acoustic structure 20 is applied to different sound field environments.

[0093] In this embodiment, the acoustic horn is upgraded from a fixed component to a "tunable" device. By changing the aspect ratio of the outlet mechanically or modularly, the anisotropy of the sound field can be adjusted in real time or offline, allowing the same flowmeter to dynamically adapt to various sound field environment requirements, greatly enhancing the product's versatility and adaptability.

[0094] In one embodiment, the sensor array having a symmetrical arrangement in the XY plane includes: the sensor structure 10 including a thin-film sensor located at the center of the inlet end; or, the sensor structure 10 including multiple thin-film sensors arranged in an array, the multiple thin-film sensors in the array located at the center of the inlet end. In the XY plane, the spacing between the multiple thin-film sensors in the X direction is 'a', the spacing between the multiple thin-film sensors in the Y direction is 'b', and a = b.

[0095] This embodiment specifically defines two implementation methods for the symmetrical arrangement of thin-film sensors (single sensor center arrangement and array equidistant center arrangement). It provides clear and unambiguous technical criteria and ensures that the sound source is symmetrical about the speaker axis. This symmetry is the basis for generating a stable and predictable sound field, simplifying the acoustic modeling and performance prediction process.

[0096] In one embodiment, the sensor array has an asymmetric arrangement in the XY plane, comprising: a sensor structure 10 including a plurality of thin-film sensors arranged in an array, the array of thin-film sensors being located at the center of the inlet end. In the XY plane, the spacing between the plurality of thin-film sensors in the X direction is 'a', the spacing between the plurality of thin-film sensors in the Y direction is 'b', and a ≠ b.

[0097] This embodiment specifically defines a key implementation method for the asymmetric arrangement of thin-film sensors (array with unequal spacing). It provides an effective means of actively introducing the directionality of the sound source. By intentionally setting unequal sensor spacing, the directivity of the sound field can be initially shaped without increasing the complexity of the speaker, providing richer initial conditions for subsequent co-design with the speaker.

[0098] In one embodiment, the thin-film sensor is a piezoelectric MEMS thin-film sensor or a flexible piezoelectric thin-film sensor.

[0099] In this embodiment, the specific type of thin-film sensor is a piezoelectric MEMS thin-film sensor or a flexible piezoelectric thin-film sensor. This type of thin-film sensor can take full advantage of the wider initial sound field angle, easier integration with microstructures, and potential flexibility compared to traditional ceramic bulk sensors, providing a material basis for fabricating a miniaturized, low-power sensor structure 10 that is easy to couple with a complex-shaped speaker.

[0100] In one embodiment, when the thin-film sensors are arranged in an array, the sound field angle can be electronically adjusted by controlling the excitation mode of the array in conjunction with the acoustic horn.

[0101] In this embodiment, multiple arrayed thin-film sensors can be electronically excited to control the parameter adjustment of the array sensors, thereby achieving electronic adjustment of the sound field angle. This embodiment adds electronic adjustment to the mechanical adjustment. By changing the excitation phase, amplitude, or timing of different sensors in the thin-film sensor array, dynamic, inertia-free scanning or switching of the sound field angle can be achieved, providing the possibility for adaptive flow measurement or multi-mode detection.

[0102] In one embodiment, the sensor structure 10 and the acoustic structure 20 are integrated and packaged into a single transducer unit that can be installed as a whole.

[0103] In this embodiment, the core functional units of the sensor structure 10 and the acoustic structure 20 are integrated into an independent transducer module, which can improve the reliability (reducing docking loss), consistency (calibration and matching are completed before leaving the factory) and ease of use (facilitating installation and replacement) of the ultrasonic gas flow meter 100, and reduce the difficulty of on-site assembly and the requirements for installation accuracy.

[0104] Please see Figure 8a and Figure 8b , Figure 8a This is a schematic diagram of the sound field angle in the XZ plane for an ultrasonic gas flow meter that does not have an acoustic structure in the prior art, or where the sensor structure and the acoustic structure are not adjusted and configured. Figure 8b This is a schematic diagram of the sound field angle in the YZ plane for an ultrasonic gas flow meter that does not have an acoustic structure in the prior art, or where the sensor structure and the acoustic structure are not adjusted and configured. Figure 8a and Figure 8b The X-axis represents the equivalent transformation of angles from 0° to 180°. The Y-axis represents the signal strength at different equivalent transformation positions. Figure 8a and Figure 8b The sound field angle in the middle has a significant deviation ( Figure 8a and Figure 8b The peak negative pressure intensity varies at different equivalent transformation locations.

[0105] In one specific embodiment of this application, the following is adopted: Figure 7a , Figure 7b , Figure 7c The acoustic structure 20 shown forms an ultrasonic gas flow meter 100. This ultrasonic gas flow meter 100 is formed as follows: Figure 9a and Figure 9b The sound field angle shown. Figure 9a For this application Figures 7a-7c The diagram shows the sound field angle of an ultrasonic gas flow meter with adjustable sound field angle in the XZ plane. Figure 9b For this application Figures 7a-7c The diagram shows the sound field angle of an ultrasonic gas flow meter with adjustable sound field angle in the YZ plane. Figure 9a and Figure 9b The X-axis represents the equivalent transformation of angles from 0° to 180°. The Y-axis represents the signal strength at different equivalent transformation positions. Figure 9a and Figure 9b It can be clearly seen that the ultrasonic gas flow meter 100 formed by adding acoustic structure 20 has its sound field angles converged to a similar level in both directions. Figure 9a and Figure 9b The peak negative pressure intensities at different equivalent transformation positions are extremely similar.

[0106] Please see Figure 10 , Figure 10 This is a schematic diagram of the structure of an ultrasonic gas flow meter 100 provided in one embodiment of the present application, applied to a reflective ultrasonic gas flow meter. Figure 10 The ultrasonic gas flow meter 100 includes: a sensor structure 10, an acoustic structure 20, a test body 30, a first connecting body 31, a second connecting body 32, and a test pipe 40. This ultrasonic gas flow meter 100 is a reflective ultrasonic gas flow meter, or a "V"-shaped ultrasonic gas flow meter, or a "Z"-shaped ultrasonic gas flow meter. Figure 10 As shown, the ultrasonic gas flow meter 100 can be integrated into the test pipeline 40 through the first connector 31 and the second connector 32 to test the fluid to be tested in the test pipeline 40.

[0107] The ultrasonic gas flow meter 100 employs a dual-diameter acoustic structure 20 to carry a miniature thin-film sensor chip (sensor structure 10), and is optimized in conjunction with the mechanical structure of the test pipe 40 to reduce the impact of beam drift on the signal when the flow velocity increases, thereby improving measurement accuracy and expanding the flow measurement range. It achieves both fluid stability and good acoustic gain. Furthermore, by designing the sensor structure 10 and acoustic structure 20 according to the technical solutions in any of the above embodiments, it can be adapted to test pipes of different sizes.

[0108] Please see Figure 11 , Figure 11 This is a schematic diagram of the structure of an ultrasonic gas flow meter 100 provided in one embodiment of this application, applied to a through-beam ultrasonic gas flow meter.

[0109] The ultrasonic gas flow meter 100 includes: a sensor structure 10, an acoustic structure 20, a fluid stabilization structure 20a, a rectifier 50, and a test body 30. The rectifier 50 includes a rectifier body 51 and a rectifier channel 52.

[0110] The test body 30 provides a flow channel for the fluid to be tested. The shape of the test body 30 is variable; it can be a cylindrical pipe, a cuboid pipe, or other regular / irregular pipes. The dimensions of the test body 30 can also be varied according to the actual application scenario. Furthermore, the inner diameter of the test body 30 can be variable. For example, the test body 30 may include a first pipe section with a first diameter, a second pipe section with a changing diameter, and a third pipe section with a second diameter, wherein the end face diameter of one end of the second pipe section with the changing diameter is equal to the first diameter, and the end face diameter of the other end of the second pipe section with the changing diameter is equal to the second diameter. In an embodiment where the inner diameter of the test body 30 is variable, two sensors are respectively disposed on the first and second pipe sections, and the two sensors can form an opposing beam. The rectifier 50 can be movably mounted on the test body 30. The rectifier 50 can also be fixedly mounted on the test body 30.

[0111] The sensor structure 10, rectifier 50, and test body 30 can be pre-integrated. Users do not need to separately install and calibrate complex rectifiers, sensor mounts, and sensors on-site. Furthermore, there are various ways to mount the sensor structure 10 to the acoustic structure 20, to mount the sensor structure 10 and acoustic structure 20 to the rectifier 50, and to mount the rectifier 50 to the test body 30 (e.g., snap-fit, adhesive, etc.), simplifying the installation process. When mounted on the rectifier 50, the fluid to be measured flows from the acoustic structure 20 to the fluid stabilization structure 20a. In some embodiments, the sensor structure 10 is directly projected, applicable to through-beam ultrasonic gas flow meters. In other embodiments, the sensor structure 10 is obliquely projected, applicable to reflective ultrasonic gas flow meters 100. Furthermore, by designing the sensor structure 10 and acoustic structure 20 according to the technical solutions in any of the above embodiments, it is possible to adapt to test pipes of different sizes.

[0112] This application also provides a method for adjusting the sound field angle of the ultrasonic gas flow meter 100 in any of the above embodiments, comprising the following steps:

[0113] S01, determine the required target sound field angle based on the acoustic path design requirements of the target pipeline.

[0114] S01, by adjusting at least one design parameter of the acoustic structure 20 and / or the sensor structure 10, the final output sound field angle of the ultrasonic gas flow meter 100 is changed to adapt to the acoustic path design requirements of the target pipeline.

[0115] This embodiment provides a systematic sound field angle adjustment process: transforming "adjustable" hardware capabilities into a repeatable and optimizable application method. Users can reverse-engineer the required sound field angle based on the specific pipeline acoustic path, and then achieve matching by adjusting the publicly available design parameters, thereby ensuring optimal performance in any specific installation. This realizes a conceptual shift from adapting the hardware (sensor structure 10 and acoustic structure 20) structure to the fluid pipeline to customizing the sound field for a specific fluid pipeline.

[0116] In one embodiment, the sound field angle adjustment method of the ultrasonic gas flow meter 100 further includes: optimizing the sound field characteristics by adjusting the operating parameters or excitation mode of the thin-film sensor.

[0117] This embodiment adds a step of auxiliary optimization using electrical parameters, which can take advantage of the sensor's adjustability. Based on the mechanical structure adjustment, the output sound field angle can be fine-tuned by adjusting the sensor's operating frequency, voltage, or excitation waveform to compensate for environmental changes, device aging, or further optimize the signal-to-noise ratio, achieving a higher level of fine-tuning of performance.

[0118] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. An ultrasonic gas flow meter, comprising: The sensor structure and acoustic structure are characterized in that the sound field angle of the ultrasonic gas flow meter is adjustable; The sensor structure includes one or more thin-film sensors; The acoustic structure includes an acoustic horn for beamforming the sound waves emitted or received by the thin-film sensor. The sensor structure and / or the acoustic structure are adjustable. At least one design parameter of the sensor structure and / or the acoustic structure can be adjusted according to different pipe structures and installation conditions to change the final sound field angle output by the ultrasonic gas flow meter. The design parameters of the sensor structure include: the number of thin-film sensors and the spacing between the thin-film sensors; The acoustic horn includes: an inlet end, an outlet end, and a transition section connecting the inlet end and the outlet end; the sensor structure is disposed at the inlet end, and the outlet end faces the pipe structure. The design parameters of the acoustic structure include: the size of the inlet end, the size of the outlet end, and the shape or variation trend of the transition section; The sensor structure includes a sensor array; the sensor array is a thin-film sensor with a multi-diaphragm structure, and / or multiple thin-film sensors with a single-diaphragm structure; The projection profile of the outlet end of the acoustic loudspeaker in the XY plane has a first distance in the X direction and a second distance in the Y direction. The magnitude of the sound field angle ultimately output by the ultrasonic gas flow meter is related to the symmetry of the sensor array arrangement in the XY plane, and the ratio between the first distance and the second distance.

2. The ultrasonic gas flow meter according to claim 1, characterized in that, The sensor array is symmetrically arranged in the XY plane, and the first distance is equal to the second distance, so that the final output sound field is an isotropic sound field.

3. The ultrasonic gas flow meter according to claim 1, characterized in that, The sensor array is asymmetrically arranged in the XY plane, the first distance and the second distance are not equal, and their design parameters are configured to compensate each other, so that the final output sound field is symmetrical in the XZ plane and the YZ plane, and the output sound field of the ultrasonic gas flow meter is an isotropic sound field.

4. The ultrasonic gas flow meter according to claim 1, characterized in that, The sensor array is symmetrically arranged in the XY plane, and the first distance and the second distance are not equal, so that the sound field angle in the X direction and the sound field angle in the Y direction of the final output sound field are different, and the output sound field of the ultrasonic gas flow meter is anisotropic.

5. The ultrasonic gas flow meter according to claim 1, characterized in that, The sensor array is asymmetrically arranged in the XY plane, and the first distance and the second distance at the outlet of the acoustic horn are not equal. The design parameters of both are configured to make the final output sound field asymmetrical in the XZ plane and the YZ plane, and the output sound field of the ultrasonic gas flow meter is an anisotropic sound field.

6. The ultrasonic gas flow meter according to any one of claims 1 to 5, characterized in that, The ratio of the first distance to the second distance can be adjusted according to the design requirements of the output sound field when the acoustic structure is applied to different sound field environments.

7. The ultrasonic gas flow meter according to claim 2 or 4, characterized in that, The sensor array is symmetrically arranged in the XY plane, including: The sensor structure includes a thin-film sensor located at the center of the inlet end; or, The sensor structure includes multiple thin-film sensors arranged in an array, with the array of thin-film sensors located at the center of the inlet end; in the XY plane, the distance between the multiple thin-film sensors in the X direction is a, and the distance between the multiple thin-film sensors in the Y direction is b, and a=b.

8. The ultrasonic gas flow meter according to claim 3 or 5, characterized in that, The sensor array has an asymmetric arrangement in the XY plane, including: The sensor structure includes multiple thin-film sensors arranged in an array, with the array of thin-film sensors located at the center of the inlet end; in the XY plane, the distance between the multiple thin-film sensors in the X direction is a, and the distance between the multiple thin-film sensors in the Y direction is b, and a≠b.

9. The ultrasonic gas flow meter according to any one of claims 1-5, characterized in that, The thin-film sensor is a piezoelectric MEMS thin-film sensor or a flexible piezoelectric thin-film sensor.

10. The ultrasonic gas flow meter according to any one of claims 1-5, characterized in that, When the thin-film sensors are arranged in an array, the sound field angle can be electronically adjusted by controlling the excitation mode of the array in conjunction with the acoustic horn.

11. The ultrasonic gas flow meter according to any one of claims 1-5, characterized in that, The sensor structure and the acoustic structure are integrated and packaged into a single transducer unit that can be installed as a whole.

12. A method for adjusting the sound field angle of an ultrasonic gas flow meter according to any one of claims 1-11, characterized in that, Including the following steps: Determine the required target sound field angle based on the acoustic path design requirements of the target pipeline; By adjusting at least one design parameter of the acoustic structure and / or the sensor structure, the final output sound field angle of the ultrasonic gas flow meter is changed to adapt to the acoustic path design requirements of the target pipeline.

13. The method for adjusting the sound field angle of an ultrasonic gas flow meter according to claim 12, characterized in that, Also includes: The acoustic field characteristics can be optimized by adjusting the operating parameters or excitation mode of the thin-film sensor in the sensor structure.

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