Flow measuring device and method fusing ultrasonic time difference and expandable to shallow and narrow river

Abstract

The application belongs to the technical field of river flow measurement, and particularly discloses a flow measuring device and method fusing ultrasonic time difference and being expandable to shallow and narrow river channels. The device comprises a frame arranged in a river channel, a plurality of vertical columns and a plurality of horizontal rods, the plurality of vertical columns and the plurality of horizontal rods form a cubic structure; an ultrasonic sensor comprising an ultrasonic transmitter and an ultrasonic receiver; at least two composite adjusting assemblies arranged on the vertical columns or the horizontal rods, the ultrasonic transmitter and the ultrasonic receiver are respectively connected with the adjusting end of one composite adjusting assembly, the position and the posture of the ultrasonic transmitter and the ultrasonic receiver are adjusted, and the alignment of the ultrasonic transmitter and the ultrasonic receiver is realized; an oscilloscope electrically connected with the ultrasonic transmitter and the ultrasonic receiver respectively; and a controller electrically connected with the composite adjusting assemblies, the oscilloscope, the ultrasonic transmitter and the ultrasonic receiver respectively. The application has the advantages of simple structure, easy operation and high speed measurement precision.

Description

Technical Field

[0001] This invention belongs to the field of river flow measurement technology, and relates to a flow measurement device and method that integrates ultrasonic time difference and can be extended to shallow and narrow rivers. Background Technology

[0002] Flow measurement is a crucial part of hydrological surveys and an essential task for conducting hydrological analysis and water resource management. It helps to understand changes in river flow, predict flood risks, and optimize water resource allocation.

[0003] Currently, the "Specification for River Flow Measurement (GB50179-2015)" and the "Technical Guidelines for Water Quality Sampling (HJ494-2009)" are the current standard requirements for river flow velocity measurement and water quality monitoring sampling, and provide relatively clear requirements for cross-sectional velocity measurement and sampling location determination.

[0004] In river cross-section velocity measurement, the current meter method is the most widely used and mature method. Sources of measurement error include insufficient number of velocity measurement verticals, limited measurement points and insufficient measurement time, depth measurement errors, and an insufficient number of measurement points on the velocity measurement verticals. The selection of a current meter-based measurement scheme should be based on the station's accuracy category, different water level levels, and data application, analyzing and determining the number of cross-section verticals (m), the number of vertical measurement points (p), and the measurement time (t). For hydrological stations where simplified analysis is feasible and higher accuracy is required, a multi-line, multi-point, long-duration measurement scheme can be selected. Regarding the number of cross-section vertical measurements (p), to avoid the random errors of the few-point method significantly affecting the cross-sectional flow, only the two-point method (during free-flowing periods) or the three-point method (during ice-covered periods) should be used. On verticals with highly irregular velocity distribution, provided the water depth is sufficient, the five-point method is suitable during free-flowing periods, and the six-point method is suitable during ice-covered periods.

[0005] On the other hand, the "Technical Guidelines for Water Quality Sampling (HJ494-2009)" clearly states that: 1) Sampling on bridges should be used as much as possible instead of riverbank sampling; 2) Sampling points need to be fixed (for comparison of samples from different times); 3) Sampling should be carried out under isodynamic conditions. If this is not possible, a series of samples can be taken from the entire cross-section of the fluid; 4) Stratified cross-section sampling can meet the sampling requirements of stratified water bodies due to different densities; 5) The water environment monitoring cross-section should be consistent with the hydrological flow measurement cross-section in order to utilize its hydrological parameters and achieve the combination of water quality monitoring and water quantity monitoring.

[0006] In general, suspension measurement can be chosen for small watersheds in cold and arid areas of northern China (where the deepest point is generally less than 2m, and during the smooth flow period, personnel can enter the river to conduct selected cross-section measurements) or when there is a measuring bridge. Based on the actual situation, the velocity measurement vertical line is usually set up using a three-point method (relative water depth positions of 0.2, 0.6, and 0.8m); the water quality monitoring vertical line sampling point is a single point (0.5m below the water surface; when the water depth is less than 1m, the test is set at 1 / 2 of the water depth). Given a fixed number of velocity measurement points, maintaining the velocity measurement depth at multiple points on the same vertical line within the same cross-section is crucial to avoiding errors. Simultaneous multi-point flow measurement has not been mentioned, as it relates to the efficiency of field operations. Furthermore, conducting flow measurement and sampling simultaneously on the same cross-section can meet the consistency requirements between water environment monitoring cross-sections and hydrological flow measurement cross-sections, allowing for the combined application of water quality and water quantity monitoring using hydrological parameters.

[0007] Flow measurement technology has undergone decades of development, resulting in numerous specific techniques. From the perspective of measurement principles, flow measurement techniques are implemented through the velocity-area method or hydraulic methods. Hydraulic methods are primarily represented by flow measurement using hydraulic structures and weirs / channels, and are tailored to specific working conditions. Velocity-area methods can be further divided into cross-sectional velocity methods and surface velocity methods based on their measurement principles. For example, current meter measurement and ultrasonic flow measurement belong to cross-sectional velocity methods, while radar and video flow measurement belong to surface velocity methods. The current meter method and buoy method are the national recommended standards in the "River Flow Measurement Standard (GB50179-2015)," while the gradient-area method, hydraulic structure flow measurement method, and acoustic Doppler method are recommended standards in the water conservancy industry. Other methods have seen limited application and experimental research. Based on whether hydrological monitoring involves direct contact with the water body, methods can be categorized into three types: "direct contact methods," "partial contact methods," and "non-contact methods." Electromagnetic methods are non-contact methods, while buoy methods and gradient-area methods are partial contact methods. Most other testing methods are direct contact methods. Non-contact technologies, as emerging methods, include ultrasonic, laser, radar, and video imaging technologies. Non-contact water measurement technology, representing the future direction of flow measurement in irrigation areas, has already seen applications in these areas, offering advantages such as being unaffected by water bodies and ease of installation and removal. However, it still lags behind contact-based water measurement technologies in terms of accuracy and reliability. Therefore, the development of water measurement instruments and equipment should be further expanded while maintaining a balance between technological cost and data accuracy.

[0008] The velocity-area method is often used to calibrate other water measurement methods due to its high measurement accuracy. However, its complex operation and long time consumption result in low flow measurement efficiency. With the increasing maturity of technologies such as ultrasound, it can be used to measure flow rates in complex flow conditions. The velocity distribution law serves as the basis for the velocity-area method of water measurement. By utilizing the velocity distribution law, the relationship between point velocity and cross-sectional average velocity can be established. Then, the cross-sectional flow rate can be obtained through point velocity, and the functional relationship between the velocity at key points and the cross-sectional average velocity can be explored, which can provide convenience for rapid flow measurement. In contrast, the water level-flow rate method is significantly affected by cross-sectional parameters and is only applicable to specific working conditions, thus making it difficult to promote.

[0009] In summary, every flow measurement technology has its optimal application scenarios and limitations. Currently, no single flow measurement technology can meet all flow measurement needs. The development of flow measurement technology can only improve its applicability as much as possible, but flow measurement accuracy remains the primary indicator in flow measurement tasks. The development of flow measurement technology is moving towards higher accuracy and lower uncertainty. Therefore, selecting the most accurate flow measurement technology possible according to local conditions is a necessary requirement for all flow measurement tasks. Thus, efficient, accurate, and highly applicable flow measurement methods have become a key technical challenge. For natural rivers characterized by narrow channels, shallow water levels, high sediment content, and frequent overflows due to heavy rains / flash floods, traditional flow measurement methods such as the buoy method, current meter method, and flowmeter method are insufficient for these scenarios, and efficient and accurate flow measurement remains a challenge. Summary of the Invention

[0010] The purpose of this invention is to provide a flow measurement device and method that integrates ultrasonic time difference and can be extended to shallow and narrow waterways, thereby solving the aforementioned technical problems.

[0011] To achieve the above objectives, the specific technical solution provided by the present invention is as follows:

[0012] A flow measurement device incorporating ultrasonic transit time and scalable to shallow and narrow waterways includes:

[0013] A frame, designed for installation in a river channel, consists of multiple columns and multiple crossbars forming a cubic structure.

[0014] An ultrasonic sensor, comprising an ultrasonic transmitter and an ultrasonic receiver;

[0015] At least two composite adjustment components are disposed on the column or the crossbar. The ultrasonic transmitter and the ultrasonic receiver are respectively connected to the adjustment end of one of the composite adjustment components to adjust the position and orientation of the ultrasonic transmitter and the ultrasonic receiver, so as to achieve the alignment of the ultrasonic transmitter and the ultrasonic receiver.

[0016] An oscilloscope is electrically connected to the ultrasonic transmitter and ultrasonic receiver, respectively.

[0017] The controller is electrically connected to the composite adjustment component, oscilloscope, ultrasonic transmitter, and ultrasonic receiver, respectively. It is used to control the composite adjustment component to adjust the position and orientation of the ultrasonic transmitter and ultrasonic receiver to form multiple pairing states. In each pairing state, the controller controls the ultrasonic transmitter to emit an ultrasonic signal that passes through the water flow cross section. The ultrasonic receiver receives the ultrasonic signal and synchronously sends it to the oscilloscope. The controller extracts the signal from the oscilloscope and processes it into the flow velocity of the water flow in that pairing state. The flow velocities obtained in multiple pairing states are averaged to obtain the average flow velocity of the river cross section. Based on the river cross section area and the average flow velocity, the flow rate of the river cross section is determined.

[0018] Furthermore, the composite adjustment component includes:

[0019] Multiple linear displacement components are arranged one-to-one on the column or crossbar. Each linear displacement component has a moving part, and the moving direction of the moving part is parallel to the length direction of the column or crossbar it is located.

[0020] The attitude adjustment assembly has a fixed end and an adjustment end, wherein the fixed end is fixedly connected to the moving part;

[0021] A clamping assembly is disposed on the adjustment end, and the ultrasonic transmitter and ultrasonic receiver are optionally detachably connected to one of the clamping assemblies.

[0022] An angle measuring component, electrically connected to the controller, is mounted on the clamping assembly and is used to measure the pitch angle of the ultrasonic transmitter or ultrasonic receiver.

[0023] Furthermore, the linear displacement component includes:

[0024] A linear motor, wherein the fixing component of the linear motor is fixedly connected to the column or the crossbar, and the moving component of the linear motor is fixedly connected to the fixed end of the attitude adjustment assembly.

[0025] Furthermore, the attitude adjustment component includes:

[0026] The first servo motor is fixed on the moving part of the linear motor. The output shaft of the first servo motor is perpendicular to the moving direction of the moving part of the linear motor and is used to adjust the circumferential angle of the ultrasonic transmitter or ultrasonic receiver.

[0027] The second servo is used to adjust the pitch angle of the ultrasonic transmitter or ultrasonic receiver. The second servo is circumferentially fixedly connected to the output shaft of the first servo. The output shaft of the second servo is perpendicular to the output shaft of the first servo. The clamping assembly is disposed circumferentially on the output shaft of the second servo.

[0028] Furthermore, the clamping assembly is an electric chuck, which is electrically connected to the controller, and the central axis of the electric chuck is perpendicular to the output shaft of the second servo motor.

[0029] Furthermore, it also includes at least one sampling bottle, which is mounted on the uprights or crossbars of the frame.

[0030] Furthermore, the plurality of the uprights and the plurality of the crossbars are telescopic rod structures.

[0031] A flow measurement method, based on the aforementioned fusion ultrasonic time-of-flight measurement device and scalable to shallow and narrow rivers, includes the following steps:

[0032] Place the frame in the river channel, with one of the opposite faces of the frame perpendicular to the direction of the water flow;

[0033] The position of the ultrasonic transmitter or the ultrasonic receiver is adjusted by using a linear displacement component, and the attitude of the ultrasonic transmitter or the ultrasonic receiver is adjusted by using an attitude adjustment component, so as to align the ultrasonic transmitter and the ultrasonic receiver and form a position pairing state.

[0034] In paired state, the controller controls the ultrasonic transmitter to emit ultrasonic signals, and the ultrasonic signals passing through the water flow section are received by the ultrasonic receiver and synchronously transmitted to the oscilloscope.

[0035] The controller acquires the straight-line distance between the ultrasonic transmitter and the ultrasonic receiver, the pitch angle measured by the angle measurement component, extracts the signal from the oscilloscope, and processes the above information into the flow rate of the water.

[0036] The water flow cross section is divided into multiple layers, and the flow velocity of the water flow at multiple locations under paired conditions is obtained in each layer.

[0037] The average flow velocity of the river cross section is obtained by averaging the flow velocities of the water flow in all paired states at all locations.

[0038] The flow rate of the river section is determined based on the cross-sectional area of ​​the river channel and the average flow velocity.

[0039] Furthermore, the flow velocity of the water is determined based on the following formula:

[0040]

[0041] in, V It is the flow velocity at a point on the sounding profile. θ It is the angle between the ultrasonic wave path and the direction of water flow. T It is the propagation time when flowing downstream. TIt is the propagation time when moving against the current. L It is the straight-line distance between the ultrasonic transmitter and the ultrasonic receiver.

[0042] Furthermore, the flow rate at the river cross-section is determined based on the following formula:

[0043]

[0044] in, Q The flow rate at the river cross-section. h It is the interval between each layer. v i It is the average flow velocity between each layer. b i It is the channel width corresponding to the average flow velocity at each level. It refers to the number of floors.

[0045] Compared with existing technologies, the present invention provides a flow measurement device and method that integrates ultrasonic time difference and is scalable to shallow and narrow rivers. The device includes a cubic frame for positioning in the river channel. An ultrasonic transmitter and an ultrasonic receiver are arranged opposite each other on the frame. At least two composite adjustment components are arranged on the frame. The ultrasonic transmitter and the ultrasonic receiver are each connected to the adjustment end of one of the composite adjustment components to adjust the position and orientation of the ultrasonic transmitter and the ultrasonic receiver, thereby achieving alignment of the ultrasonic transmitter and the ultrasonic receiver. The ultrasonic transmitter and the ultrasonic receiver are electrically connected to an oscilloscope. The composite adjustment components, the oscilloscope, and the ultrasonic... The transmitter and ultrasonic receiver are electrically connected to the controller. The controller controls the composite adjustment component to adjust the position and orientation of the ultrasonic transmitter and ultrasonic receiver to form multiple pairing states. In each pairing state, the ultrasonic transmitter is controlled to emit an ultrasonic signal that passes through the cross-section of the water flow. The ultrasonic receiver receives the ultrasonic signal and synchronously sends it to the oscilloscope. The controller extracts the signal from the oscilloscope and processes the signal into the flow velocity of the water flow in that pairing state. The flow velocities obtained in multiple pairing states are averaged to obtain the average flow velocity of the river cross-section. Based on the cross-sectional area of ​​the river and the average flow velocity, the flow rate of the river cross-section is determined. This invention addresses the characteristics of natural rivers, such as narrow channels, shallow water levels, high sediment content, and frequent overflows due to torrential rains and flash floods. By combining the ultrasonic time-of-flight method with the velocity-area method, it enables multi-point positioning and flow measurement on the same sounding section. It boasts advantages such as simple structure, ease of operation, and high velocity measurement accuracy. It allows for the analysis and research of water-sediment characteristics in typical watersheds, aiming to provide a scientific basis for a deeper understanding of the dynamic changes in water and sediment, predicting future water and sediment trends, and flood control and disaster reduction. With strong practicality, it is worthy of widespread promotion. Attached Figure Description

[0046] Figure 1 This is a schematic diagram of the overall structure of the present invention.

[0047] Figure 2 This is a schematic diagram illustrating the principle of the ultrasonic sensor of the present invention.

[0048] Figure 3 This is a schematic diagram of the oscilloscope used in this invention.

[0049] Figure 4 This is a schematic diagram of the flow measurement method of the present invention.

[0050] Figure 5 This is a schematic diagram of the flow velocity calculation and sliding process of the present invention, which collects 15 points at a time.

[0051] Figure 6 This is a partial structural diagram of the present invention. Figure 1 .

[0052] Figure 7 This is a partial structural diagram of the present invention. Figure 2 . Detailed Implementation

[0053] To address the technical problem that traditional flow measurement devices and methods cannot be applied to natural rivers in the semi-arid regions of northern China, this invention provides a flow measurement device that integrates ultrasonic time difference and can be extended to shallow and narrow river channels.

[0054] To enable those skilled in the art to better understand and implement the technical solutions of this invention, the following will be combined with... Figures 1 to 7 The technical solutions in this invention will be described clearly and in detail.

[0055] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and are not intended to 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 invention.

[0056] Furthermore, it should be further explained that in the description of the embodiments of the present invention, unless otherwise stated, " / " means "or". For example, A / B can mean A or B. The "and / or" in the text is merely a description of the relationship between related objects, indicating that there can be three relationships. For example, A and / or B can mean: A exists alone, A and B exist simultaneously, and B exists alone. In addition, in the description of the embodiments of the present invention, "multiple" means two or more.

[0057] The terms "first," "second," "third," and "fourth" are used for descriptive purposes only and should not be construed as implying or suggesting relative importance or implicitly indicating the number of indicated technical features. Thus, a feature defined as "first," "second," "third," or "fourth" may explicitly or implicitly include one or more of that feature, and in the description of this invention, unless otherwise stated, "multiple" means two or more.

[0058] Example 1

[0059] like Figure 1 As shown, this invention provides a flow measurement device that integrates ultrasonic time-of-flight measurement and is scalable to shallow and narrow rivers. It includes a frame 1 for installation in the river channel. The frame 1 has multiple columns and multiple crossbars, forming a cubic structure. The frame 1 is made of stainless steel. The cubic structure of the frame 1 facilitates the acquisition of flow velocities at different points. By obtaining the point flow velocities, the cross-sectional flow rate can be obtained, thereby exploring the functional relationship between the flow velocity at key points and the average cross-sectional flow velocity, thus providing a solution for rapid and accurate flow measurement.

[0060] To avoid the stainless steel frame 1 affecting the propagation of ultrasonic waves, the ultrasonic sensor 2 is a split type, comprising an ultrasonic transmitter 201 and an ultrasonic receiver 202, which are electrically connected to an oscilloscope. In practical applications, the appropriate ultrasonic velocity measurement combination can be selected based on the propagation characteristics of ultrasonic waves in clean / turbid water. These ultrasonic velocity measurement combinations include different frequency ranges and different output powers.

[0061] On a column or crossbar, the ultrasonic transmitter 201 and the ultrasonic receiver 202 are respectively connected to the adjustment end of a composite adjustment component 3 to adjust the position and orientation of the ultrasonic transmitter 201 and the ultrasonic receiver 202, so as to achieve alignment of the ultrasonic transmitter 201 and the ultrasonic receiver 202.

[0062] The controller is electrically connected to the composite adjustment assembly 3, the oscilloscope, the ultrasonic transmitter 201, and the ultrasonic receiver 202, respectively. It is used to control the composite adjustment assembly 3 to adjust the position and orientation of the ultrasonic transmitter 201 and the ultrasonic receiver 202 to form multiple pairing states. In each pairing state, the controller controls the ultrasonic transmitter 201 to emit an ultrasonic signal that passes through the water flow cross section. The ultrasonic receiver 202 receives the ultrasonic signal and synchronously sends it to the oscilloscope. The controller extracts the signal from the oscilloscope and processes the signal into the flow velocity of the water flow in the pairing state. The flow velocities obtained in the multiple pairing states are averaged to obtain the average flow velocity of the river cross section. Based on the river cross section area and the average flow velocity, the flow rate of the river cross section is determined.

[0063] Specifically, the aforementioned composite adjustment assembly 3 includes multiple linear displacement assemblies 31 that are correspondingly mounted on the column or crossbar. Each linear displacement assembly 31 has a moving part, and the moving direction of the moving part is parallel to the length direction of the column or crossbar it is located. The attitude adjustment assembly 32 has a fixed end and an adjustment end. Its fixed end is fixedly connected to the moving part, and a clamping assembly is fixed on the adjustment end. The ultrasonic transmitter 201 and the ultrasonic receiver 202 are each optionally detachably connected to a clamping assembly.

[0064] An angle measuring component, electrically connected to the controller, is mounted on the clamping assembly and is used to measure the pitch angle of the ultrasonic transmitter 201 or the ultrasonic receiver 202.

[0065] More specifically, linear displacement components 31 are installed on multiple columns and multiple crossbars. The linear displacement components 31 are implemented by linear motors. The fixing parts of the linear motors are fixedly connected to the columns or crossbars, and the moving parts of the linear motors are fixedly connected to the fixed end of the attitude adjustment components 32. The linear motors are coordinated and controlled by the controller to control the movement and position locking. Multiple target positions can be set to achieve high-precision repeatable positioning of multiple points.

[0066] Furthermore, such as Figure 6 and Figure 7 As shown, the attitude adjustment assembly 32 includes a first servo motor 321 and a second servo motor 322. The first servo motor 321 is fixed to the moving part of the linear motor, and its output shaft is perpendicular to the moving direction of the linear motor, used to adjust the circumferential angle of the ultrasonic transmitter 201 or the ultrasonic receiver 202. The second servo motor 322 is used to adjust the pitch angle of the ultrasonic transmitter 201 or the ultrasonic receiver 202. The second servo motor 322 is circumferentially fixedly connected to the output shaft of the first servo motor 321, and its output shaft is perpendicular to the output shaft of the first servo motor 321. A clamping assembly is disposed circumferentially on the output shaft of the second servo motor 322.

[0067] Furthermore, the clamping assembly is an electric chuck, which is electrically connected to the controller, and the central axis of the electric chuck is perpendicular to the output axis of the second servo motor 322.

[0068] Furthermore, it also includes at least one sampling bottle, which is set on the uprights or crossbars of frame 1. The sampling bottle is placed on the side of the cubic frame 1 and fixed to the uprights or crossbars using positioning clamps to ensure that the sampling bottle is firmly fixed to frame 1. The opening of the sampling bottle faces the direction of water flow against the water flow to ensure that water flows into the sampling bottle with the water flow. In addition, it should be noted that when arranging the sampling bottle, the requirements of symmetry and structural stability should be considered as much as possible. This not only avoids swaying caused by eccentric loads, but also shortens the sampling path, improves sampling efficiency and positioning accuracy, and provides a good foundation for achieving multi-point consistent sampling.

[0069] Furthermore, multiple columns and multiple crossbars are telescopic rod structures, which are set up as telescopic rod structures to adjust the size and match different river width conditions.

[0070] A flow measurement method, based on the aforementioned fusion ultrasonic time-of-flight measurement device and scalable to shallow and narrow rivers, includes the following steps:

[0071] Place frame 1 in the river channel, with one of the opposite faces of frame 1 perpendicular to the direction of water flow;

[0072] The position of the ultrasonic transmitter 201 or the ultrasonic receiver 202 is adjusted by using the linear displacement component 31, and the attitude adjustment component 32 is used to adjust the attitude of the ultrasonic transmitter 201 or the ultrasonic receiver 202, so as to achieve alignment of the ultrasonic transmitter 201 and the ultrasonic receiver 202 and form a position pairing state.

[0073] In paired state, the controller controls the ultrasonic transmitter 201 to emit ultrasonic signals, and the ultrasonic signals passing through the water flow section are received by the ultrasonic receiver 202 and synchronously sent to the oscilloscope.

[0074] The controller acquires the straight-line distance between the ultrasonic transmitter 201 and the ultrasonic receiver 202, the pitch angle measured by the angle measurement component, and the signal from the oscilloscope. It processes the above information into the flow velocity of the water flow, divides the water flow cross-section into multiple layers, acquires the flow velocity of the water flow in the paired state at multiple locations in each layer, and averages the flow velocities of the water flow in the paired state at all locations to obtain the average flow velocity of the river cross-section. Based on the river cross-sectional area and the average flow velocity, the flow rate of the river cross-section is determined.

[0075] Furthermore, the flow velocity of the water is determined based on the following formula:

[0076]

[0077] in, V It is the flow velocity at a point on the sounding profile. θ It is the angle between the ultrasonic wave path and the direction of water flow.T 1 It is the propagation time when flowing downstream. T 2 It is the propagation time when moving against the current. L It is the straight-line distance between the ultrasonic transmitter 201 and the ultrasonic receiver 202.

[0078] Furthermore, the flow rate at the river cross-section is determined based on the following formula:

[0079]

[0080] in, Q The flow rate at the river cross-section. h It is the interval between each layer. v i It is the average flow velocity between each layer. b i It is the channel width corresponding to the average flow velocity at each level. It refers to the number of floors.

[0081] Furthermore, it should be noted that during the experiment, to avoid the stainless steel frame 1 affecting the propagation of ultrasonic waves, the ultrasonic sensor 2 was selected as a separate unit, with the ultrasonic transmitter 201 and ultrasonic receiver 202 set apart and connected to the same oscilloscope. When calculating the flow coefficient using the time-of-flight ultrasonic method, many factors such as water temperature and sediment content can cause fluctuations in the calculated river flow velocity results. Therefore, during calibration, the actual temperature range should be considered when adjusting the measurement parameters. Ultrasonic sensors 2 at 1 MHz and 750 kHz were used during non-flood and flood seasons, respectively, to control the influence of sediment content on river flow velocity. To reduce the impact of the number of flow velocity measurement verticals on the randomness and systematic errors of the flow measurement, the width between each flow measurement vertical needs to be optimized. The arrangement principles of the flow measurement verticals are shown in Table 1.

[0082] A flow measurement device incorporating ultrasonic time difference and extendable to shallow and narrow rivers is placed in the river. Utilizing the principle that ultrasonic waves travel faster and take less time in downstream flow than upstream flow, the time difference between upstream and downstream ultrasonic waves is obtained, and this difference is used to calculate the river cross-sectional velocity. The principle is explained in [link to principle]. Figure 2 .

[0083] The position of the ultrasonic transmitter 201 or the ultrasonic receiver 202 is adjusted by a linear motor, and the transmission / reception direction of the ultrasonic transmitter 201 or the ultrasonic receiver 202 is adjusted by the attitude adjustment component 32. In this way, the flow velocity at different points on the sounding vertical line on the sounding section is measured, and then the average flow velocity of the river section is obtained. Finally, the area of ​​the river section is calculated by the length and width of the river section using the traditional cross-section measurement method. According to the formula [Q=A*V], the flow rate of the river section is obtained. A water level-flow rate curve can also be plotted based on the measured flow rate and water level.

[0084] Combining ultrasonic flow measurement technology with the flow-area method can yield more accurate and reliable flow measurement results. The flow velocity at different layers of the same cross section can be calculated using the ultrasonic time-of-flight method, and the flow rate of the entire cross section can be obtained using the multi-layer flow velocity-area method. This step can be completed manually or by using dedicated software as input data. It should be noted that when calculating manually, the specific points and layer calculation formulas in Table 2 can be used as a reference.

[0085] Table 1. Principles and Basis for Vertical Line Arrangement

[0086]

[0087] Note: The selection criteria for flow measurement points are: straight, representative river channels without reservoirs or other water conservancy facilities.

[0088] For situations where the river channels are narrow and the water level is shallow within the basin, the flow velocity is determined based on the ultrasonic time-of-flight method:

[0089]

[0090] in, V It is the flow velocity at a point on the sounding profile. θ It is the angle between the ultrasonic wave path and the direction of water flow. T 1 It is the propagation time when flowing downstream. T 2 It is the propagation time when moving against the current. L It is the straight-line distance between the ultrasonic transmitter 201 and the ultrasonic receiver 202.

[0091] This invention utilizes, for example Figure 2 The flow velocity is measured by utilizing the principle that ultrasonic waves travel for different times in forward and reverse water flows. The ultrasonic time-of-flight method, with fixed distance and angle, precisely controls the receiving relationship between the ultrasonic transmitter 201 and the ultrasonic receiver 202, their straight-line distance, and the angle between them and the water flow direction. θThis ensures the transmission and acquisition of ultrasonic waves even in turbulent water flow. After activating the ultrasonic transmitter 201 and ultrasonic receiver 202, the time it takes for the ultrasonic wave to travel from the transmitter 201 to the receiver 202 is determined by analyzing the waveforms on the oscilloscopes connected to the transmitter and receiver 202. This allows us to obtain the propagation times of the ultrasonic wave in downstream flow (A→C) and upstream flow (C→A). T 1 and T 2 .

[0092] Based on the set angle and length, the flow velocity at 15 points as shown in Table 2 can be collected at once. When the initial position of the ultrasonic transmitter 201 is at point A and the initial position of the ultrasonic receiver 202 is at point C, the angle of the ultrasonic transmitter 201 and the ultrasonic receiver 202 is adjusted using the composite adjustment component 3 so that the ultrasonic transmitter 201 and the ultrasonic receiver 202 are on the same straight line. The oscilloscope is turned on and the waveform on the oscilloscope is observed, and the time between the forward and reverse flow is recorded. The flow velocity at point Z, the midpoint of AC, is measured according to the flow measurement formula. The ultrasonic transmitter 201 is stationary at point A, and the ultrasonic receiver 202 is moved along direction ① to the midpoint M of DC. The oscilloscope is turned on and the waveform of the ultrasonic wave on the oscilloscope is observed until a regular waveform appears, such as... Figure 3 As shown, the first and second starting points of the defined regular shape represent the working time of the ultrasonic transmitter 201 and the ultrasonic receiver 202. At this time, the flow velocity at point Y, the midpoint of AM, is measured. The ultrasonic transmitter 201 moves along direction ② to point N, the midpoint of AB, and the ultrasonic receiver 202 is located at point C. At this time, the flow velocity at point X, the midpoint of CN, is measured. Figure 4 and Figure 5 As shown, points Z / Y / X are different flow measurement verticals located on the same horizontal plane. The average flow velocity of this horizontal plane is measured by the three-point average method. Similarly, the flow velocities at the midpoints W (CO), V (CH), T (PA), and R (AE) can be measured.

[0093] Table 2. Flow velocity calculation process and formula for collecting data from 15 points at a time.

[0094]

[0095] The cross-sectional flow rate was calculated using the cross-sectional area method, employing a multi-layer flow measurement approach to determine the flow rate at the river cross-section. Q The formula is as follows:

[0096]

[0097] in, Q The flow rate at the river cross-section. h It is the interval between each layer. vi It is the average flow velocity between each layer. b i It is the channel width corresponding to the average flow velocity at each level. It refers to the number of floors.

[0098] We stipulate that the river cross-section is divided into regular rectangles based on the points used to measure the river flow velocity using the ultrasonic time-of-flight method. The width of the river cross-section 4 is defined as the length of the stainless steel frame 1, which is 50cm. The average flow velocity point of each layer corresponds to the width of the river cross-section of that layer. The height of the average flow velocity point of the cross-section is the interval between each layer, which is 12.5cm. The flow rate of the entire cross-section is calculated using an integral algorithm.

[0099] The average flow velocity of each river cross-section is obtained using the ultrasonic transit-time method. The flow rate of the entire cross-section is then calculated by combining the ultrasonic transit-time method with the velocity-area method. Since there are multiple velocity points for each layer using the ultrasonic transit-time method, we stipulate that the average value is taken as the flow velocity of that layer.

[0100] Taking points X, Y, and Z as examples, the average flow velocity of the river cross-section shown below is obtained using the ultrasonic time-of-flight method:

[0101]

[0102] The average flow velocity of the river cross-section is obtained by combining the velocity-area method formula with the ultrasonic transit-time method, resulting in the cross-sectional flow rate shown below:

[0103]

[0104] In summary, the present invention provides a flow measurement device and method that integrates ultrasonic time difference and is scalable to shallow and narrow rivers. The device includes a cubic frame 1 for positioning in the river channel. An ultrasonic transmitter 201 and an ultrasonic receiver 202 are arranged opposite each other on the frame 1. At least two composite adjustment components 3 are provided on the frame 1. The ultrasonic transmitter 201 and the ultrasonic receiver 202 are respectively connected to the adjustment end of one of the composite adjustment components 3 for adjusting the position and orientation of the ultrasonic transmitter 201 and the ultrasonic receiver 202 to achieve alignment of the ultrasonic transmitter 201 and the ultrasonic receiver 202. The ultrasonic transmitter 201 and the ultrasonic receiver 202 are electrically connected to an oscilloscope. The composite adjustment components 3... An oscilloscope, an ultrasonic transmitter 201, and an ultrasonic receiver 202 are electrically connected to a controller. The controller controls the composite adjustment assembly 3 to adjust the position and orientation of the ultrasonic transmitter 201 and the ultrasonic receiver 202 to form multiple paired states. In each paired state, the ultrasonic transmitter 201 emits an ultrasonic signal that passes through the water flow cross-section. The ultrasonic receiver 202 receives the ultrasonic signal and synchronously sends it to the oscilloscope. The controller extracts the signal from the oscilloscope and processes it into the flow velocity of the water flow in that paired state. The flow velocities obtained in multiple paired states are averaged to obtain the average flow velocity of the river cross-section. Based on the river cross-sectional area and the average flow velocity, the flow rate of the river cross-section is determined. This invention addresses the characteristics of natural rivers, such as narrow channels, shallow water levels, high sediment content, and frequent overflows due to torrential rains and flash floods. By combining the ultrasonic time-of-flight method with the velocity-area method, it enables multi-point positioning and flow measurement on the same sounding section. It boasts advantages such as simple structure, ease of operation, and high velocity measurement accuracy. It allows for the analysis and research of water-sediment characteristics in typical watersheds, aiming to provide a scientific basis for a deeper understanding of the dynamic changes in water and sediment, predicting future water and sediment trends, and flood control and disaster reduction. With strong practicality, it is worthy of widespread promotion.

[0105] It is understood that the present invention has been described through some embodiments, and those skilled in the art will know that various changes or equivalent substitutions can be made to these features and embodiments without departing from the spirit and scope of the present invention.

[0106] Furthermore, based on the teachings of this invention, modifications can be made to these features and embodiments to adapt to specific situations and materials without departing from the spirit and scope of the invention. Therefore, this invention is not limited to the specific embodiments disclosed herein, and all embodiments falling within the scope of the claims are protected by this invention.

Claims

1. A flow measurement device integrating ultrasonic time-of-flight measurement and scalable to shallow and narrow rivers, characterized in that, include: The frame (1) is used to be set in the river channel and has multiple columns and multiple crossbars, which together form a cubic structure. An ultrasonic sensor (2) includes an ultrasonic transmitter (201) and an ultrasonic receiver (202). At least two composite adjustment components (3) are set on the column or the crossbar. The ultrasonic transmitter (201) and the ultrasonic receiver (202) are respectively connected to the adjustment end of one of the composite adjustment components (3) to adjust the position and attitude of the ultrasonic transmitter (201) and the ultrasonic receiver (202) to achieve the alignment of the ultrasonic transmitter (201) and the ultrasonic receiver (202). An oscilloscope is electrically connected to the ultrasonic transmitter (201) and ultrasonic receiver (202), respectively; The controller is electrically connected to the composite adjustment component (3), oscilloscope, ultrasonic transmitter (201) and ultrasonic receiver (202) respectively. It is used to control the composite adjustment component (3) to adjust the position and orientation of the ultrasonic transmitter (201) and ultrasonic receiver (202) to form multiple pairing states. In each pairing state, the controller controls the ultrasonic transmitter (201) to emit an ultrasonic signal that passes through the cross-section of the water flow. The ultrasonic receiver (202) receives the ultrasonic signal and synchronously sends it to the oscilloscope. The controller extracts the signal from the oscilloscope and processes the signal into the flow velocity of the water flow in the pairing state. The flow velocities of the water flow obtained in the multiple pairing states are averaged to obtain the average flow velocity of the river cross-section. Based on the cross-sectional area of ​​the river and the average flow velocity, the flow rate of the river cross-section is determined. The composite adjustment component (3) includes: Multiple linear displacement components (31) are arranged one-to-one on the column or crossbar. Each linear displacement component (31) has a moving part, and the moving direction of the moving part is parallel to the length direction of the column or crossbar on which it is located. The attitude adjustment component (32) has a fixed end and an adjustment end, the fixed end of which is fixedly connected to the moving part; A clamping assembly is provided on the adjustment end, wherein the ultrasonic transmitter (201) and the ultrasonic receiver (202) are optionally detachably connected to one of the clamping assemblies; An angle measuring component, electrically connected to the controller, is mounted on the clamping assembly and is used to measure the pitch angle of the ultrasonic transmitter (201) or the ultrasonic receiver (202).

2. The flow measurement device according to claim 1, which integrates ultrasonic time difference and is scalable to shallow and narrow rivers, is characterized in that... The linear displacement component (31) includes: A linear motor, wherein the fixing part of the linear motor is fixedly connected to the column or the crossbar, and the moving part of the linear motor is fixedly connected to the fixed end of the attitude adjustment component (32).

3. The flow measurement device according to claim 2, which integrates ultrasonic time difference and is scalable to shallow and narrow rivers, is characterized in that... The attitude adjustment component (32) includes: The first servo motor (321) is fixed on the moving part of the linear motor. The output shaft of the first servo motor (321) is perpendicular to the moving direction of the moving part of the linear motor and is used to adjust the circumferential angle of the ultrasonic transmitter (201) or the ultrasonic receiver (202). The second servo (322) is used to adjust the pitch angle of the ultrasonic transmitter (201) or the ultrasonic receiver (202). The second servo (322) is circumferentially fixedly connected to the output shaft of the first servo (321). The output shaft of the second servo (322) is perpendicular to the output shaft of the first servo (321). The clamping assembly is disposed in the circumferential direction of the output shaft of the second servo (322).

4. The flow measurement device according to claim 3, which integrates ultrasonic time difference and is scalable to shallow and narrow rivers, is characterized in that... The clamping assembly is an electric chuck, which is electrically connected to the controller, and the central axis of the electric chuck is perpendicular to the output axis of the second servo motor (322).

5. The flow measurement device fused with ultrasonic time difference according to claim 1 or 4 and scalable to shallow and narrow rivers, characterized in that, It also includes at least one sampling bottle, which is set on the uprights or crossbars of the frame (1).

6. The flow measurement device according to claim 5, which integrates ultrasonic time difference and is scalable to shallow and narrow rivers, is characterized in that... The plurality of columns and the plurality of crossbars are telescopic rod structures.

7. A flow measurement method, based on the flow measurement device of claim 1 that integrates ultrasonic time difference and is scalable to shallow and narrow rivers, characterized in that, Includes the following steps: Place the frame (1) in the river channel, with one of the opposite faces of the frame (1) perpendicular to the direction of the water flow; The position of the ultrasonic transmitter (201) or the ultrasonic receiver (202) is adjusted by using the linear displacement component (31), and the attitude of the ultrasonic transmitter (201) or the ultrasonic receiver (202) is adjusted by using the attitude adjustment component (32), so as to achieve alignment of the ultrasonic transmitter (201) and the ultrasonic receiver (202) and form a position pairing state. In the paired state, the controller controls the ultrasonic transmitter (201) to emit ultrasonic signals. The ultrasonic signals passing through the water flow section are received by the ultrasonic receiver (202) and synchronously transmitted to the oscilloscope. The controller acquires the straight-line distance between the ultrasonic transmitter (201) and the ultrasonic receiver (202), the pitch angle measured by the angle measurement component, extracts the signal from the oscilloscope, and processes the above information into the flow rate of the water. The water flow cross section is divided into multiple layers, and the flow velocity of the water flow at multiple locations under paired conditions is obtained in each layer. The average flow velocity of the river cross section is obtained by averaging the flow velocities of the water flow in all paired states at all locations. The flow rate of the river section is determined based on the cross-sectional area of ​​the river channel and the average flow velocity.

8. The flow measurement method according to claim 7, characterized in that, The velocity of the water flow is determined based on the following formula: in, V It is the flow velocity at a point on the sounding profile. θ It is the angle between the ultrasonic wave path and the direction of water flow. T 1 It is the propagation time when flowing downstream. T 2 It is the propagation time when moving against the current. L It is the straight-line distance between the ultrasonic transmitter (201) and the ultrasonic receiver (202).

9. The flow measurement method according to claim 7, characterized in that, The flow rate at a river cross-section is determined based on the following formula: in, Q The flow rate at the river cross-section. h It is the interval between each layer. v i It is the average flow velocity between each layer. b i It is the channel width corresponding to the average flow velocity at each level. It refers to the number of floors.

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