Ultrasonic flow velocity measurement system, method and device

Abstract

The present invention discloses an ultrasonic flow rate measurement system, including an annular slideway that can be sleeved on a fluid pipeline; an ultrasonic transducer pair that can slide on the annular slideway, the ultrasonic transducer pair including two ultrasonic transducers that transmit and receive ultrasonic signals; the ultrasonic transducer pair is used to form multiple sound channels with different distances from the central axis of the fluid pipeline in the fluid pipeline by sliding two ultrasonic transducers on the annular slideway, and detect the time difference corresponding to the fluid flow rate on each sound channel to obtain the fluid flow rate of the cross section of the fluid pipeline. In the present application, the annular slideway can be sleeved on the fluid pipeline, and the ultrasonic transducer can slide on the annular slideway to realize the measurement of multiple sound channels. In terms of technology to ensure measurement accuracy, the number of ultrasonic transducers used is reduced, thereby greatly reducing the measurement cost. The present application also provides an ultrasonic flow rate measurement method and device, which have the above-mentioned beneficial effects.

Description

Technical Field

[0001] The present invention relates to the technical field of fluid flow velocity measurement, and in particular to an ultrasonic flow velocity measurement system, method and device. Background Art

[0002] In the industrial field, the straight pipe section of the fluid pipeline generally does not meet the requirements of four in front and two in the back. At the same time, there are many interfering devices (such as valves, elbows, reducers and other devices) in the upstream straight pipe section of the fluid. With the changes in working conditions or loads, the flow field of the medium fluid in the large-diameter fluid pipeline is turbulent, the velocity field distribution is distorted, and pulse vortices exist. This makes it technically difficult to accurately measure the flow rate of the medium fluid in large-diameter pipelines.

[0003] Ultrasonic transducers are devices made of piezoelectric materials that can convert electrical energy into ultrasonic energy, and transmit it into the fluid being measured and receive it by the receiver, forming a sound channel between the transmitting end and the receiving end of the ultrasonic wave. When the sound channel and the fluid flow velocity are not perpendicular to each other, the fluid velocity at the midpoint of the sound channel can be determined based on the time difference from the ultrasonic wave being transmitted to being received on the sound channel.

[0004] However, since the flow field in the fluid pipeline is complex and the velocity field is distorted, it is generally necessary to use multiple channels to measure multiple fluid velocities and then perform comprehensive analysis to obtain the final fluid velocity. Obviously, to measure the fluid velocities corresponding to multiple channels, multiple sets of ultrasonic transducers are required, and the price of ultrasonic transducers is relatively high, which invisibly increases the measurement cost of the fluid velocity in the fluid pipeline. Summary of the invention

[0005] The purpose of the present invention is to provide an ultrasonic flow velocity measurement system, method and device, which greatly reduce the cost of fluid flow velocity measurement.

[0006] In order to solve the above technical problems, the present invention provides an ultrasonic flow velocity measurement system, comprising an annular slideway that can be sleeved on a fluid pipeline; an ultrasonic transducer pair that can slide on the annular slideway, the ultrasonic transducer pair comprising two ultrasonic transducers for transmitting and receiving ultrasonic signals;

[0007] The ultrasonic transducer pair is used to form a plurality of sound channels at different distances from the central axis of the fluid pipeline in the fluid pipeline by sliding the two ultrasonic transducers on the annular slideway, and detect the time difference corresponding to the fluid flow rate on each of the sound channels to obtain the fluid flow rate of the cross section of the fluid pipeline.

[0008] Optionally, the annular slide is an elliptical slide, and the inner ring minor axis of the elliptical slide is equal to the radius of the outer wall of the fluid pipeline.

[0009] Optionally, the annular slideway is a circular slideway whose inner ring radius is equal to the outer wall radius of the fluid pipeline; the number of the annular slideways is not less than two, and the number of the ultrasonic transducer pairs is at least one pair;

[0010] Wherein, a pair of ultrasonic transducers is formed between two ultrasonic transducers on different annular slideways.

[0011] Optionally, the number of the annular slideways is two, the number of the ultrasonic transducer pairs is two, and two ultrasonic transducers are arranged on each of the two annular slideways.

[0012] Optionally, it also includes a temperature-pressure-flow integrated device for detecting the fluid temperature, fluid pressure and fluid flow rate in the fluid pipeline.

[0013] The present application also provides an ultrasonic flow velocity measurement method, comprising:

[0014] Collecting time differences obtained by detecting multiple different sound channels formed by an ultrasonic transducer pair in a fluid pipeline, wherein an annular slideway is sleeved on the fluid pipeline, and two ultrasonic transducers of the ultrasonic transducer pair for transmitting and receiving ultrasonic signals are sequentially moved to different positions on the annular slideway to form the sound channels with different distances from the central axis of the fluid pipeline;

[0015] Determine the average flow velocity corresponding to each of the sound channels according to the corresponding relationship between the time difference and the fluid flow velocity;

[0016] The fluid flow rate of the cross section of the fluid pipeline is obtained according to the respective average flow rates.

[0017] Optionally, collecting the time difference obtained by detecting a plurality of different sound channels formed in the fluid pipeline by an ultrasonic transducer comprises:

[0018] The time difference obtained by detecting a plurality of X-shaped sound channels formed by the ultrasonic transducer pair is collected, wherein each of the X-shaped sound channels includes two mutually intersecting sound channels, and the planes where the X-shaped sound channels are located are parallel to each other and to the central axis of the fluid pipeline, and the distances between the X-shaped sound channels and the central axis of the fluid pipeline are different.

[0019] Optionally, before collecting the time difference, the method further includes:

[0020] detecting fluid fluctuation level data in the fluid pipeline;

[0021] determining a fluctuation state of the fluid according to the fluid fluctuation level data;

[0022] If the fluctuation state of the fluid is a stable state, the time difference obtained by the ultrasonic transducer for detecting a plurality of different sound channels formed in the fluid pipeline includes:

[0023] According to the preset positions of each sound channel, the ultrasonic transducer pair is moved on the annular slideway in sequence to the position points corresponding to each sound channel position, and the time difference corresponding to each sound channel position is detected;

[0024] Obtaining the fluid flow rate of the cross section of the fluid pipeline according to the average flow rate calculations, comprising:

[0025] A weighted operation is performed on each of the average flow velocities to obtain the fluid flow velocity.

[0026] Optionally, if the fluid is in a periodic fluctuation state, the acquisition of the time difference obtained by detecting a plurality of different sound channels formed in the fluid pipeline by the ultrasonic transducer includes:

[0027] According to the preset positions of each sound channel, the ultrasonic transducer pair is moved on the annular slide to the position points corresponding to each sound channel position in sequence, and the time difference corresponding to each sound channel position is detected at the same period time point in the fluctuation cycle of the fluid.

[0028] Optionally, if the fluctuation state of the fluid is an unsteady state, the acquisition of the time difference obtained by detecting a plurality of different sound channels formed in the fluid pipeline by the ultrasonic transducer includes:

[0029] Sliding the ultrasonic transducer pair to a plurality of different positions on the annular slideway in sequence to form a plurality of X-shaped sound channels parallel to each other, and the spacing between each of the X-shaped sound channels is no greater than a preset spacing;

[0030] Obtaining the fluid flow rate of the cross section of the fluid pipeline according to the average flow rate calculations, comprising:

[0031] Based on the cross-sectional flow velocity formula Combine the average flow velocities to obtain the cross-sectional flow velocity of the fluid pipeline. Among them, v i is the average flow velocity measured by the X-shaped sound channel formed by sliding the ultrasonic transducer pair for the i-th time; b is the distance between the X-shaped sound channels formed by two adjacent times; D is the cross-sectional diameter of the fluid pipeline; and n is the integer of D / b.

[0032] The present application also provides an ultrasonic flow velocity measuring device, comprising:

[0033] A collection module, used for collecting time differences obtained by detecting a plurality of different sound channels formed by an ultrasonic transducer pair in a fluid pipeline, wherein an annular slideway is sleeved on the fluid pipeline, and two ultrasonic transducers of the ultrasonic transducer pair for transmitting and receiving ultrasonic signals are sequentially moved to different positions on the annular slideway to form the sound channels having different distances from the central axis of the fluid pipeline;

[0034] A first calculation module, used for determining an average flow velocity corresponding to each of the sound channels according to a corresponding relationship between the time difference and the fluid flow velocity;

[0035] The second calculation module is used to calculate and obtain the fluid flow rate of the cross section of the fluid pipeline according to each of the average flow rates.

[0036] An ultrasonic flow velocity measurement system provided by the present invention comprises an annular slideway which can be sleeved on a fluid pipeline; an ultrasonic transducer pair which can slide on the annular slideway, the ultrasonic transducer pair comprising two ultrasonic transducers for transmitting and receiving ultrasonic signals; the ultrasonic transducer pair is used to form a plurality of sound channels at different distances from the central axis of the fluid pipeline in the fluid pipeline by sliding the two ultrasonic transducers on the annular slideway, and detect the time difference corresponding to the fluid flow velocity on each sound channel to obtain the fluid flow velocity of the cross section of the fluid pipeline.

[0037] The ultrasonic flow rate measurement system provided in the present application includes an annular slide that can be sleeved on a fluid pipeline, and an ultrasonic transducer pair can slide on the annular slide. Accordingly, when the positions of the ultrasonic transducer pair on the annular slide are different, different sound channels can be formed, that is to say, a pair of ultrasonic transducers can realize flow rate measurement of multiple different sound channels. Compared with the prior art of arranging a large number of ultrasonic transducers on the periphery of the fluid pipeline to realize the measurement of multiple sound channels, the present application can reduce the number of ultrasonic transducers used in ensuring the measurement accuracy, thereby greatly reducing the measurement cost.

[0038] The present application also provides an ultrasonic flow velocity measurement method and device, which have the above-mentioned beneficial effects. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to more clearly illustrate the embodiments of the present invention or the technical solutions of the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0040] Figure 1 This is a schematic diagram of the principle of ultrasonic flow velocity measurement using the time difference method;

[0041] Figure 2 It is a schematic diagram of the layout of an ultrasonic transducer for ultrasonic flow velocity measurement using the time difference method in the prior art;

[0042] Figure 3 A schematic diagram of the structure of an ultrasonic flow velocity measurement system provided in an embodiment of the present application;

[0043] Figure 4 A schematic diagram of the structure of the annular slide provided in the embodiment of the present application

[0044] Figure 5 A schematic diagram of a flow chart of an ultrasonic flow velocity measurement method provided in an embodiment of the present application;

[0045] Figure 6 Another schematic diagram of the ultrasonic flow velocity measurement method provided in the embodiment of the present application;

[0046] Figure 7 A schematic diagram of the framework structure of the ultrasonic flow velocity measurement device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0047] like Figure 1 As shown, Figure 1 The schematic diagram of the principle of ultrasonic flow velocity measurement using the time difference method is shown in Figure 1. Ultrasonic transducers A and B are installed upstream and downstream of the measured medium with a flow velocity of v. The ultrasonic wave emitted by ultrasonic transducer A is modulated by the fluid and then received by ultrasonic transducer B. The propagation time is recorded as t 顺 ; Conversely, ultrasonic transducer B sends and ultrasonic transducer A receives, and we can get t 逆 . It is known that L is two t 顺 The distance between them, c represents the speed of sound, v represents the flow velocity of the fluid, and θ is the angle between the sound channel and the central axis of the pipe 10. The time difference between the two channels for the two ultrasonic waves from the time of sending to the time of receiving can be expressed as: Among them, v 2 cos 2 θ vs c 2 is much smaller, so v can be ignored 2 cos 2 θ, note is K1 (calibrated at different temperatures and pressures), then the average linear velocity of the sound channel is: v = K1*Δt.

[0048] However, because the medium fluid in the pipeline 10 may have flow disturbances, distorted velocity field distribution, and pulse vortices, the average velocity obtained by measuring with only a pair of ultrasonic transducers is insufficient to reflect the average flow velocity of the entire cross section. Figure 2As shown, conventional ultrasonic flow velocity measurement using the time difference method often arranges multiple pairs of ultrasonic transducers 11 on the outer surface of the pipeline 10, and obtains the average flow velocity of the fluid cross section based on multiple average flow velocities determined by each pair of ultrasonic transducers 11.

[0049] Although more pairs of ultrasonic transducers 11 can more accurately measure the fluid flow rate, the high price of ultrasonic transducers 11 will increase the cost of the entire measurement system. In addition, for flow rate measurement with complex flow field changes, more pairs of ultrasonic transducers 11 are required. Obviously, this does not take advantage of the wide application of time difference method ultrasonic flow rate measurement.

[0050] To this end, the present application provides a technical solution for reducing the measurement cost of ultrasonic flow velocity measurement using the time difference method while ensuring measurement accuracy.

[0051] In order to enable those skilled in the art to better understand the scheme of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific implementation methods. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0052] like Figure 3 As shown, Figure 3 A schematic diagram of the structure of an ultrasonic flow velocity measurement system provided in an embodiment of the present application, the system may include:

[0053] An annular slideway 12 that can be sleeved on the fluid pipeline 10; an ultrasonic transducer pair that can slide on the annular slideway 12, the ultrasonic transducer pair including two ultrasonic transducers 11 for transmitting and receiving ultrasonic signals;

[0054] The ultrasonic transducer pair is used to form multiple sound channels with different distances from the central axis of the fluid pipeline 10 in the fluid pipeline 10 by sliding two ultrasonic transducers 11 on the annular slide, and detect the time difference corresponding to the fluid flow rate on each sound channel to obtain the fluid flow rate of the cross section of the fluid pipeline 10.

[0055] refer to Figure 3There are two annular slideways 12 sleeved on the fluid pipeline 10, and each annular slideway 12 is provided with two ultrasonic transducers 11, and each ultrasonic transducer 11 can slide on the annular slideway 12 along the outer side of the fluid pipeline 10. The four ultrasonic transducers 11 can be slid to the same horizontal plane, so that the four ultrasonic transducers 11 can form two mutually intersecting sound channels, and the two sound channels form an X-shaped structure. Then two average flow velocities can be measured based on these two sound channels. Then the four ultrasonic transducers 11 are translated up and down by the same height as a whole, and two mutually intersecting sound channels are also formed, but the distance of the sound channels relative to the central axis of the fluid pipeline 10 changes. According to the same principle, two average flow velocities can also be measured. By analogy, when the ultrasonic transducer 11 is slid to different positions on the annular slideway 12, the measurable sound channels and the central axis of the fluid pipeline 10 are at different distances from each other. The average flow velocity of each corresponding sound channel is comprehensively analyzed based on the average flow velocities of multiple sound channels to obtain the average flow velocity of the cross section of the fluid pipeline 10.

[0056] It can be seen that in the ultrasonic flow velocity measurement system provided in the present embodiment, by sleeved the annular slide 12 on the fluid pipeline 10 of the flow velocity to be measured, and by sliding the position of the ultrasonic transducer 11 on the annular slide 12, the measurement of the average flow velocity of the fluid on multiple different sound channels can be achieved. Compared with the prior art method of arranging a large number of ultrasonic transducers 11 around the entire fluid pipeline to achieve the detection of the average flow velocity of multiple sound channels, the present application arranges a slidable ultrasonic transducer 11 on the annular slide 12, which can also measure the average flow velocity of multiple sound channels at different positions, and greatly reduces the number of ultrasonic transducers 11, thereby greatly reducing the cost of measuring the fluid flow velocity in the fluid pipeline 10.

[0057] Understandably, Figure 3 The arrangement of the annular slideway 12 and the ultrasonic transducer 11 shown is only a specific implementation of the present application. In practical applications, there are many different arrangements of the annular slideway 12 and the ultrasonic transducer 11.

[0058] exist Figure 3In the embodiment, the annular slide 12 is a circular track, and the inner diameter of the annular slide 12 is the same as the radius of the outer wall of the fluid pipeline 10, and the two annular slides 12 are arranged in parallel, and each annular slide 12 is provided with two ultrasonic transducers to form two pairs of ultrasonic transducer pairs. However, in actual applications, two pairs of ultrasonic transducers 11 are not necessarily provided on the annular slide 12. For example, one ultrasonic transducer 11 can be provided on each annular slide 12. First, the two ultrasonic transducers 11 are respectively slid to positions a1 and b2 to achieve the measurement of the sound channel between positions a1 and b2, and then the two ultrasonic transducers 11 are respectively slid to positions a2 and b1 to achieve the measurement of the sound channel between positions a2 and b1. Obviously, the sound channel between positions a1 and b2 and the sound channel between positions a2 and b1 are equivalent to two mutually intersecting X-shaped sound channels. Similarly, the detection of X-shaped sound channels at other distances from the fluid pipeline 10 can be achieved in a similar manner.

[0059] because Figure 3 The description is made by taking the fluid pipeline 10 as an example of being placed horizontally. In actual application, as long as the plane where the X-shaped sound channel is located is parallel to the central axis of the fluid pipeline 10, it will suffice.

[0060] The ultrasonic transducers 11 on the annular slide 12 can be one pair or two pairs, and more than two pairs of ultrasonic transducers 11 are not excluded, and the technical solution of the present application can be realized. However, the more pairs of ultrasonic transducers 11 there are, the higher the cost is, but the measurement efficiency is higher, and multi-channel flow velocity measurement can be performed simultaneously. Therefore, in actual application, the actual number of pairs of ultrasonic transducers 11 can be selected according to actual needs, and this application does not limit it.

[0061] It can be seen that in an optional embodiment of the present application, the annular slide 12 can be a circular slide with an inner ring radius equal to the outer wall radius of the fluid pipeline; the number of annular slides 12 is not less than two, the number of pairs of ultrasonic transducers 11 is at least one pair; and a pair of ultrasonic transducers is formed between two ultrasonic transducers 11 on different annular slides 12.

[0062] Optionally, the annular slide 12 in the present application is not necessarily a circular slide, but may also be an elliptical slide.

[0063] In an optional embodiment of the present application, the annular slideway 12 is an elliptical slideway, and the inner ring minor axis of the elliptical slideway is equal to the outer wall radius of the fluid pipeline 10. Then when the elliptical slideway is sleeved on the fluid pipeline 10, the plane where the elliptical slideway is located should form an acute angle of less than 90 degrees with the central axis of the fluid pipeline 10.

[0064] At this time, the number of the elliptical slide can be only one, and there can be only one pair of ultrasonic transducers 11 on the elliptical slide. The two ultrasonic transducers 11 can be symmetrically arranged about the short axis of the elliptical slide to form a sound channel to measure an average flow rate, and then the elliptical slide is rotated with the short axis as the rotation center axis. When the elliptical slide fits the fluid pipeline 10 again, the sound channels of the two ultrasonic transducers 11 and the sound channels before the rotation of the elliptical slide intersect with each other, and are at the same distance from the center axis of the fluid pipeline 10. After two average flow rate measurements are achieved in the above manner, the two ultrasonic transducers 11 can be moved up and down by a certain distance to measure sound channels at different heights in turn.

[0065] It is understandable that the number of ultrasonic transducers 11 provided on the elliptical slide is not limited to one pair, but may include multiple pairs, which is not specifically limited in the present application.

[0066] Furthermore, the number of elliptical slides is not limited to one, and two identical elliptical slides can be arranged crosswise, and the short axes of the two elliptical slides are coaxial. At least one pair of ultrasonic transducers 11 is arranged on each elliptical slide, and multi-channel flow velocity measurement can be achieved by moving the positions of the ultrasonic transducers 11 on each elliptical slide.

[0067] The difference between the elliptical slide and the circular slide is that, because the plane of the elliptical slide is at an acute angle to the central axis of the fluid pipeline 10, a sound channel is formed between two ultrasonic transducers 11 on the same elliptical slide, while because the plane of the circular slide is perpendicular to the central axis of the fluid pipeline, a sound channel can be formed between two ultrasonic transducers 11 on different circular slides. Of course, the present application does not exclude the embodiment of forming a sound channel between two ultrasonic transducers 11 on different elliptical slides, as long as the sound channel passes through the medium fluid and is not perpendicular to the flow direction of the medium fluid.

[0068] It should be noted that the above embodiments are mainly described by taking the cross-section of the fluid pipeline 10 as a circular pipe as an example. In actual application, it is not excluded that the medium fluid to be measured flows in a pipe with a cross-section of a square, rectangular or other shape. Then, the shape of the annular slide 12 should also be adaptively adjusted accordingly. For example, if the cross-section of the fluid pipeline is a square, the annular slide 12 can be a square slide or a rectangular slide. There are also similar implementation methods that are not listed one by one in this application.

[0069] As mentioned above, when calculating the corresponding average flow velocity according to the time difference measured by the ultrasonic transducer, the proportional coefficient K1 involved is also related to the fluid temperature and pressure. Therefore, in order to further improve the measurement accuracy of the fluid flow velocity, the ultrasonic flow velocity measurement system of the present application may further include:

[0070] A temperature-pressure-flow integrated device used to detect fluid temperature, fluid pressure and fluid flow in fluid pipelines.

[0071] The pressure-stabilized flow integrated device can measure the fluid temperature, fluid pressure and fluid flow at a certain point in the fluid pipeline. According to the fluid temperature and fluid pressure, a more accurate proportional coefficient K1 can be determined, thereby improving the accuracy of flow velocity calculation. The fluid flow rate reflects the complexity of the flow field in the fluid pipeline. If the fluid flow field changes too complexly, the measurement position points of the ultrasonic transducer can be set more densely to measure more groups of average velocities, and finally obtain the average flow velocity that best reflects the fluid flow velocity. On the contrary, if the fluid flow field is relatively stable, the number of channels for measuring the flow velocity can be appropriately reduced. It can be seen that the temperature-pressure flow integrated device in this embodiment can provide a data basis for the calculation of the average flow velocity and how to select the measurement point of the ultrasonic transducer.

[0072] Based on any of the above embodiments, manual sliding may be used for the sliding of the ultrasonic transducer 11 on the annular slide 10. For this purpose, a scale may be provided on the annular slide 10, and the distance between the sound channel of each pair of ultrasonic transducers 11 and the central axis of the fluid pipeline 10 may be determined based on the scale. The scale may be marked in the form of a central angle relative to the starting position, an arc length relative to the starting position, etc., or may be directly marked with the distance from the central axis of the fluid pipeline 10, which is not specifically limited in the present application.

[0073] Of course, in addition to manual sliding, the ultrasonic transducer 11 can also be slid by a driving device, which can be simply connected to the ultrasonic transducer 11.

[0074] Considering that the thickness of the fluid pipeline 10 corresponding to the medium fluid to be measured may be different according to the actual pipeline conditions, in order to improve the adaptability of the ultrasonic flow velocity measurement system during use, the annular slide 10 can be set as a slide with adjustable radius to adapt to a variety of fluid pipelines of different sizes. For example, the annular slide can be set as a multi-section splicable structure, and in actual application, annular pipelines of appropriate sizes can be spliced ​​according to the size of the fluid pipeline 10.

[0075] In an optional embodiment of the present application, reference Figure 4 , Figure 4A schematic diagram of the structure of an annular slide provided in an embodiment of the present application, wherein the annular slide 12 may include a strip-shaped flexible slide 121 and a buckling structure 122;

[0076] When the strip-shaped flexible slideway 121 surrounds the fluid pipeline 10 , the buckling structure 122 is used to buckle and connect the joints of the strip-shaped flexible slideway 121 to form an annular structure.

[0077] like Figure 4 As shown, the buckling structure 122 can be a buckle structure fixedly connected to one end of the strip flexible slide 121, and the other end of the strip flexible slide 121 can pass through the buckle structure. Obviously, the length of the end of the strip flexible slide 121 passing through the buckle structure can directly adjust the size of the formed annular structure.

[0078] certainly, Figure 4 An achievable embodiment of the present application is shown in FIG. 1 . In actual application, the structure of the buckling structure 122 and the strip-shaped flexible slide 121 may also have many different embodiments, which are not listed here one by one.

[0079] In addition, for the strip-shaped flexible slide, the shape of the formed annular slide can obviously be determined according to the fluid pipeline, which further improves the applicability of the annular slide.

[0080] Based on any of the above-mentioned ultrasonic flow velocity measurement systems, the present application also provides an ultrasonic flow velocity measurement method, such as Figure 5 As shown, the measurement method may include:

[0081] S11: collecting time differences obtained by detecting multiple different sound channels formed in the fluid pipeline using an ultrasonic transducer.

[0082] Among them, an annular slide is sleeved on the fluid pipeline, and the two ultrasonic transducers in the ultrasonic transducer pair that transmit and receive ultrasonic signals move to different positions on the annular slide in sequence to form various sound channels with different distances from the central axis of the fluid pipeline.

[0083] With reference to any of the above embodiments, the ultrasonic transducer in the ultrasonic flow velocity measurement system moves on the annular slideway to form a plurality of unused sound channels, which will not be described in detail in this embodiment.

[0084] Optionally, when measuring the flow velocity of a cross section at the same position of a fluid pipeline, the time difference obtained by detecting multiple X-shaped sound channels formed by a pair of ultrasonic transducers may be collected, wherein each X-shaped sound channel includes two mutually intersecting sound channels, and the planes where the X-shaped sound channels are located are parallel to each other and to the central axis of the fluid pipeline, and the distances between each X-shaped sound channel and the central axis of the fluid pipeline are different.

[0085] Of course, the present application does not exclude the measurement method in which the X-shaped sound channels are not completely parallel to each other. For example, when the distance from the central axis of the fluid pipeline is a specific distance, multiple X-shaped sound channels that are not parallel to each other can be formed to measure multiple average flow velocities for this specific distance, thereby improving the accuracy of obtaining the flow velocity of the cross section of the fluid pipeline based on each average flow velocity.

[0086] S12: Determine the average flow velocity corresponding to each sound channel according to the corresponding relationship between the time difference and the fluid flow velocity.

[0087] The corresponding relationship between the time difference and the fluid flow rate is v = K1*Δt, where K1 is Where Δt is the time difference, c is the speed of sound, L is the length of the sound channel, and θ is the angle between the sound channel and the central axis of the fluid pipe.

[0088] Taking into account that the sound velocity c in the proportional coefficient K1 will change with the fluid temperature and pressure, therefore, the fluid temperature and fluid pressure in the fluid pipeline can be detected, and the sound velocity can be corrected based on the fluid temperature and fluid pressure, ultimately obtaining a more accurate fluid flow rate value.

[0089] S13: Obtain the fluid flow velocity of the cross section of the fluid pipeline according to the average flow velocity calculations.

[0090] In this embodiment, the ultrasonic transducers arranged on the annular slideway are moved so that the distances between the sound channel formed by the ultrasonic transducer pair and the central axis of the fluid pipeline are different. Then, the fluid flow velocities of the sound channels corresponding to the different distances are averaged to obtain the average flow velocity of the cross section of the fluid pipeline. There is no need to use a large number of ultrasonic transducers arranged on the outer surface of the fluid pipeline, which improves the measurement cost of the flow velocity of the medium fluid in the fluid pipeline to a certain extent.

[0091] Based on the above embodiments, in order to further improve the accuracy of measuring fluid flow rate, as Figure 6 As shown, the present application also provides another method for measuring the flow rate of a medium fluid in a fluid pipeline, which may include:

[0092] S21: Detect fluid fluctuation level data in the fluid pipeline.

[0093] A differential pressure Pitot tube flowmeter can be used to detect flow changes at a certain point in the collection fluid pipeline to determine the level of fluid fluctuation in the pipeline.

[0094] S22: judging the fluctuation state of the fluid according to the fluid fluctuation level data.

[0095] S23: If the fluid is in a stable state, according to the preset sound channel positions, the ultrasonic transducer is moved on the annular slide to the position points corresponding to the sound channel positions in sequence, and the time difference corresponding to the sound channel positions is detected, and then enter S25.

[0096] Because the fluid flow field is relatively stable, it is sufficient to select several sound channel positions and measure them in sequence.

[0097] S24: If the fluid is in a periodic fluctuation state, according to the pre-set sound channel positions, the ultrasonic transducer pair is moved on the annular slide to the position points corresponding to each sound channel position in turn, and the time difference corresponding to each sound channel position is detected at the same periodic time point in the fluctuation cycle of the fluid, and then enters S25.

[0098] It should be noted that for fluids in a stable state and a periodic fluctuation state, the positions of each pair of acoustic and ultrasonic transducers moving on the annular channel can be exactly the same. However, in order to avoid interference caused by fluid fluctuations when performing time difference detection on periodic fluctuation fluids, the measurement can be performed at the same time point in each fluctuation cycle. For example, the time difference can be detected at a time point of 1 / 4T or 1 / 2T in each fluctuation cycle.

[0099] S25: Determine the average flow velocity corresponding to each sound channel according to each time difference, and perform weighted operation on each average flow velocity to obtain the fluid flow velocity.

[0100] When performing weighted calculation on each average flow velocity, the corresponding weight coefficient can be set with reference to the Gauss-Legendre scheme or the OWIRS scheme, which will not be described in detail in this embodiment.

[0101] S26: If the wave state of the fluid is an unstable state, the ultrasonic transducer pair is slid to a plurality of different positions on the annular slide in sequence to form a plurality of mutually parallel X-shaped sound channels, and the spacing between each X-shaped sound channel is not greater than a preset spacing.

[0102] In actual operation, the X-shaped sound channel can be controlled to move in a direction perpendicular to the plane where the X-shaped sound channel is located. Each time it moves a predetermined distance, two groups of time differences can be measured, and then it continues to move the predetermined distance to re-measure a group of time differences. This can be repeated to measure multiple groups of time differences in the entire cross section of the fluid pipeline. The predetermined distance can be adjusted according to actual needs, but the predetermined distance should be as small as possible to improve the detection accuracy.

[0103] S27: Based on the cross-sectional flow velocity formula, the cross-sectional flow velocity of the fluid pipeline is obtained by combining the various average flow velocities.

[0104] The cross-sectional velocity formula can be: Among them, v i is the average flow velocity measured by the X-shaped sound channel formed by the i-th sliding ultrasonic transducer pair; b is the distance between two adjacent X-shaped sound channels; D is the cross-sectional diameter of the fluid pipeline; n is the integer of D / b.

[0105] In the present application, different detection methods are used for different states of fluid fluctuations in the fluid pipeline, which can avoid the interference of fluid fluctuations on fluid flow rate measurement to a certain extent and greatly improve the accuracy of fluid flow rate measurement.

[0106] The ultrasonic flow velocity measurement device provided in an embodiment of the present invention is introduced below. The ultrasonic flow velocity measurement device described below and the ultrasonic flow velocity measurement method described above can be referred to each other.

[0107] Figure 7 The structural block diagram of the ultrasonic flow velocity measuring device provided in the embodiment of the present invention is shown in FIG. Figure 7 The ultrasonic flow velocity measuring device may include:

[0108] The acquisition module 100 is used to acquire the time difference obtained by detecting a plurality of different sound channels formed by an ultrasonic transducer pair in a fluid pipeline, wherein an annular slideway is sleeved on the fluid pipeline, and two ultrasonic transducers of the ultrasonic transducer pair for transmitting and receiving ultrasonic signals are sequentially moved to different positions on the annular slideway to form the sound channels having different distances from the central axis of the fluid pipeline;

[0109] A first operation module 200, configured to determine an average flow velocity corresponding to each of the sound channels according to a corresponding relationship between the time difference and the fluid flow velocity;

[0110] The second calculation module 300 is used to calculate and obtain the fluid flow velocity of the cross section of the fluid pipeline according to each of the average flow velocities.

[0111] The ultrasonic flow velocity measuring device of the present embodiment is used to implement the aforementioned ultrasonic flow velocity measuring method. Therefore, the specific implementation of the ultrasonic flow velocity measuring device can be seen in the embodiment section of the ultrasonic flow velocity measuring method in the previous text. For example, the acquisition module 100, the first operation module 200, and the second operation module 300 are respectively used to implement steps S11 to S13 in the above-mentioned ultrasonic flow velocity measurement method. Therefore, its specific implementation can refer to the description of the corresponding embodiments of each part, which will not be repeated here.

[0112] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply that there is any such actual relationship or order between these entities or operations. Moreover, the term "include", "comprise" or any other variant thereof is intended to cover non-exclusive inclusion, so that the process, method, article or equipment that includes a series of elements are inherent to the elements. In the absence of more restrictions, the elements limited by the sentence "comprise one..." do not exclude the presence of other identical elements in the process, method, article or equipment that includes the elements. In addition, the above-mentioned technical solution provided in the embodiment of the present application is consistent with the corresponding technical solution in the prior art in principle, and the part is not described in detail, so as not to repeat too much.

[0113] In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referred to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part.

Claims

1. An ultrasonic flow velocity measurement system, characterized in that: It comprises an annular slideway which can be sleeved on a fluid pipeline; an ultrasonic transducer pair which can slide on the annular slideway, wherein the ultrasonic transducer pair comprises two ultrasonic transducers for transmitting and receiving ultrasonic signals; The ultrasonic transducer pair is used to form a plurality of sound channels at different distances from the central axis of the fluid pipeline in the fluid pipeline by sliding the two ultrasonic transducers on the annular slideway, and detect the time difference corresponding to the fluid flow velocity on each of the sound channels to obtain the fluid flow velocity of the cross section of the fluid pipeline; When the annular slide is an elliptical slide, the inner ring short axis of the elliptical slide is equal to the radius of the outer wall of the fluid pipeline; when the elliptical slide is sleeved on the fluid pipeline, the plane where the elliptical slide is located and the central axis of the fluid pipeline form an acute angle less than 90 degrees; wherein, when the number of the elliptical slides is one, and the ultrasonic transducer pair on the elliptical slide is a pair, the two ultrasonic transducers are symmetrically arranged about the short axis of the elliptical slide to form a sound channel to achieve the measurement of an average flow velocity; the elliptical slide can rotate relative to the fluid pipeline with the inner ring short axis as the rotation center axis, so that the elliptical slide fits the fluid pipeline twice in two mutually symmetrical planes centered on the short axis, and accordingly the sound channels formed by the two ultrasonic transducers before and after the rotation of the elliptical slide twice intersect with each other and are at the same distance from the central axis of the fluid pipeline; the two ultrasonic transducers can move up and down on the elliptical slide to measure sound channels of different heights in turn; When the annular slideway is a circular slideway whose inner ring radius is equal to the outer wall radius of the fluid pipeline, the number of the annular slideways is not less than two, and the number of the ultrasonic transducer pairs is at least one pair; wherein a pair of ultrasonic transducer pairs is formed between two ultrasonic transducers on different annular slideways; It also includes a temperature-pressure-flow integrated device for detecting the fluid temperature, fluid pressure and fluid flow in the fluid pipeline.

2. An ultrasonic flow velocity measurement method, characterized in that: include: Collecting time differences obtained by detecting multiple different sound channels formed by an ultrasonic transducer pair in a fluid pipeline, wherein an annular slideway is sleeved on the fluid pipeline, and two ultrasonic transducers of the ultrasonic transducer pair for transmitting and receiving ultrasonic signals are sequentially moved to different positions on the annular slideway to form the sound channels with different distances from the central axis of the fluid pipeline; Determine the average flow velocity corresponding to each of the sound channels according to the corresponding relationship between the time difference and the fluid flow velocity; Obtaining the fluid flow rate of the cross section of the fluid pipeline according to the average flow rate calculation; The annular slide is an elliptical slide, and the inner ring short axis of the elliptical slide is equal to the radius of the outer wall of the fluid pipeline; when the elliptical slide is sleeved on the fluid pipeline, the plane where the elliptical slide is located and the central axis of the fluid pipeline form an acute angle less than 90 degrees; wherein, when the number of the elliptical slides is one, and the ultrasonic transducer pair on the elliptical slide is a pair, the two ultrasonic transducers are symmetrically arranged about the short axis of the elliptical slide to form a sound channel to achieve an average flow rate measurement; the elliptical slide can rotate relative to the fluid pipeline with the inner ring short axis as the rotation center axis, so that the elliptical slide fits the fluid pipeline twice in two mutually symmetrical planes centered on the short axis, and accordingly the sound channels formed by the two ultrasonic transducers before and after the rotation of the elliptical slide twice intersect with each other and are at the same distance from the central axis of the fluid pipeline; the two ultrasonic transducers can move up and down on the elliptical slide to measure sound channels of different heights in turn; Or, the annular slide is a circular slide whose inner ring radius is equal to the outer wall radius of the fluid pipeline; the number of the annular slides is not less than two, and the number of the ultrasonic transducer pairs is at least one pair; wherein a pair of ultrasonic transducers is formed between two ultrasonic transducers on different annular slides.

3. The ultrasonic flow velocity measurement method according to claim 2, characterized in that: The time difference obtained by collecting ultrasonic transducers from detecting multiple different sound channels formed in the fluid pipeline includes: The time difference obtained by detecting a plurality of X-shaped sound channels formed by the ultrasonic transducer pair is collected, wherein each of the X-shaped sound channels includes two mutually intersecting sound channels, and the planes where the X-shaped sound channels are located are parallel to each other and to the central axis of the fluid pipeline, and the distances between the X-shaped sound channels and the central axis of the fluid pipeline are different.

4. The ultrasonic flow velocity measurement method according to claim 3, characterized in that: Before collecting the time difference, the method further includes: Detecting fluid fluctuation level data in the fluid pipeline; determining the fluctuation state of the fluid according to the fluid fluctuation level data; If the fluctuation state of the fluid is a stable state, the acquisition of the time difference obtained by the ultrasonic transducer detecting a plurality of different sound channels formed in the fluid pipeline includes: According to the preset positions of each sound channel, the ultrasonic transducer pair is moved on the annular slideway in sequence to the position points corresponding to each sound channel position, and the time difference corresponding to each sound channel position is detected; Obtaining the fluid flow rate of the cross section of the fluid pipeline according to each of the average flow rates comprises: A weighted operation is performed on each of the average flow velocities to obtain the fluid flow velocity.

5. The ultrasonic flow velocity measurement method according to claim 4, characterized in that: If the fluid is in a periodic fluctuation state, the time difference obtained by the ultrasonic transducer for detecting multiple different sound channels formed in the fluid pipeline includes: According to the preset positions of each sound channel, the ultrasonic transducer pair is moved on the annular slide to the position points corresponding to each sound channel position in sequence, and the time difference corresponding to each sound channel position is detected at the same period time point in the fluctuation cycle of the fluid.

6. The ultrasonic flow velocity measurement method according to claim 4, characterized in that: If the fluctuation state of the fluid is an unsteady state, the acquisition of the time difference obtained by the ultrasonic transducer detecting a plurality of different sound channels formed in the fluid pipeline includes: Sliding the ultrasonic transducer pair to a plurality of different positions on the annular slideway in sequence to form a plurality of X-shaped sound channels parallel to each other, and the spacing between each of the X-shaped sound channels is no greater than a preset spacing; Obtaining the fluid flow rate of the cross section of the fluid pipeline according to each of the average flow rates comprises: Based on the cross-sectional flow velocity formula , combining the average flow velocities, to obtain the cross-sectional flow velocity of the fluid conduit ;in, For the The average flow velocity measured by sliding the X-shaped sound channel formed by the ultrasonic transducer pair for a second; is the distance between two adjacent X-shaped sound channels; is the cross-sectional diameter of the fluid pipeline; for Round up.

7. An ultrasonic flow velocity measuring device, characterized in that: include: A collection module, used for collecting time differences obtained by detecting a plurality of different sound channels formed by an ultrasonic transducer pair in a fluid pipeline, wherein an annular slideway is sleeved on the fluid pipeline, and two ultrasonic transducers of the ultrasonic transducer pair for transmitting and receiving ultrasonic signals are sequentially moved to different positions on the annular slideway to form the sound channels having different distances from the central axis of the fluid pipeline; A first calculation module, used for determining an average flow velocity corresponding to each of the sound channels according to a corresponding relationship between the time difference and the fluid flow velocity; A second calculation module, used for calculating the fluid flow rate of the cross section of the fluid pipeline according to each of the average flow rates; When the annular slide is an elliptical slide, and the inner ring short axis of the elliptical slide is equal to the radius of the outer wall of the fluid pipeline; when the elliptical slide is sleeved on the fluid pipeline, the plane where the elliptical slide is located and the central axis of the fluid pipeline form an acute angle less than 90 degrees; wherein, when the number of the elliptical slides is one, and the ultrasonic transducer pair on the elliptical slide is a pair, the two ultrasonic transducers are symmetrically arranged about the short axis of the elliptical slide to form a sound channel to achieve the measurement of an average flow velocity; the elliptical slide can rotate relative to the fluid pipeline with the inner ring short axis as the rotation center axis, so that the elliptical slide fits the fluid pipeline twice in two mutually symmetrical planes centered on the short axis, and accordingly the sound channels formed by the two ultrasonic transducers before and after the rotation of the elliptical slide twice intersect with each other and are at the same distance from the central axis of the fluid pipeline; the two ultrasonic transducers can move up and down on the elliptical slide to measure sound channels of different heights in turn; When the annular slide is a circular slide whose inner ring radius is equal to the outer wall radius of the fluid pipeline; the number of the annular slides is not less than two, and the number of the ultrasonic transducer pairs is at least one pair; wherein a pair of ultrasonic transducers is formed between two ultrasonic transducers on different annular slides.

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