A device and method for real-time detection of river flow velocity and accompanying sediment.

Abstract

This invention discloses a real-time detection device and method for river flow velocity and accompanying sediment. The device includes a flow passage cylinder, a detachable filter assembly and a rotating detection assembly respectively installed at the water inlet and inside the flow passage cylinder, a rear mounting base, and a wireless transmission module. The rotating detection assembly includes a rotating shaft and force-sensing blades mounted on the shaft. When water flows through the flow passage cylinder, it drives the force-sensing blades to rotate the shaft. A rotation speed detection unit in the rear mounting base collects the rotation speed of the shaft, and a data acquisition and processing unit calculates the water flow velocity based on a calibration relationship between the rotation speed and the water flow velocity. The accompanying sediment particle impact force sensing blades generate actual impact force signals. The data acquisition and processing unit inverts the sediment particle mass based on the actual impact force signal and the current water flow velocity, and further estimates the equivalent particle size of the sediment. This device can achieve in-situ synchronous detection of river flow velocity and accompanying sediment particle size, has a simple structure, and is easy to deploy on site.

Description

Technical Field

[0001] This invention belongs to the field of river sediment size measurement technology, specifically, it relates to a real-time detection device and method for river flow velocity and accompanying sediment. Background Technology

[0002] High-sediment-laden flows not only cause reservoir siltation and riverbed uplift, but also seriously affect the safety of water conservancy projects, navigation efficiency, and the ecological environment. Meanwhile, flow velocity is a core parameter in hydrological monitoring, directly impacting flood warnings, water resource allocation, and river management. Sediment size distribution, on the other hand, determines sediment deposition rate, transport capacity, and its erosive effect on water conservancy facilities. Traditional methods often measure flow velocity and sediment separately, making it difficult to reflect their dynamic coupling relationship and hindering accurate hydrological forecasting and engineering decision-making.

[0003] Currently, the monitoring of flow velocity and sediment size mainly relies on the following technologies, but all of them have significant drawbacks:

[0004] (1) Existing flow velocity monitoring technologies mainly include rotor-type and acoustic-type. Rotor-type flow meters need to be in contact with the water flow, are easily worn by silt or entangled by aquatic plants, and have high maintenance costs; at the same time, they can only obtain single-point data and cannot reflect the cross-sectional flow velocity distribution. Acoustic Doppler flow meters can measure vertical flow velocity profiles, but sound wave attenuation is severe in water bodies with high sediment content, resulting in decreased accuracy and making them unsuitable for large-scale deployment.

[0005] (2) Existing sediment size monitoring technologies mainly include sieving-weighing method, laser particle size analyzer, and ultrasonic sand measurement technology. Sieving-weighing method requires manual sampling, and laboratory sieving takes up to several hours, making real-time feedback impossible; the sampling frequency is low, making it difficult to capture dynamic changes in sediment. Laser particle size analyzer can measure size in real time, but the optical window is easily contaminated by sediment and requires frequent cleaning; in addition, data distortion will occur under conditions of ultra-high sediment content (>10kg / m³). Ultrasonic sand measurement technology is greatly affected by bubbles and turbulence, and the size inversion algorithm relies on empirical formulas, resulting in poor universality.

[0006] (3) Joint monitoring technology

[0007] Most existing equipment measures flow velocity and sediment parameters independently, which can lead to:

[0008] 1. Data asynchrony: There is a temporal / spatial misalignment between flow velocity and sediment data, making it difficult to analyze the correlation between the two.

[0009] 2. High system complexity: Multiple instruments need to be deployed, resulting in high costs and difficult maintenance. Summary of the Invention

[0010] Purpose of the invention: The purpose of this invention is to provide a device and method for real-time detection of river flow velocity and accompanying sediment, which can simultaneously measure and provide real-time feedback on the flow velocity and the size of accompanying sediment.

[0011] Technical solution: The present invention provides a real-time detection device for river flow velocity and accompanying sediment, comprising a detachable filter assembly, a rotating detection assembly, a flow passage cylinder, a rear mounting base, and a wireless transmission module;

[0012] The flow tube is a cylindrical structure that runs from front to back, including an inlet end and an outlet end. An axially continuous water flow channel is formed inside the flow tube.

[0013] The detachable filter assembly is located at the water inlet end of the flow tube to prevent debris from entering the interior of the flow tube.

[0014] The rotating detection component is located inside the flow tube and downstream of the detachable filter assembly. The rotating detection component includes a rotating shaft and force sensing blades mounted on the rotating shaft. The force sensing blades are used to drive the rotating shaft to rotate under the action of water flow and to collect the actual impact force signal generated when sediment particles hit the force sensing blades.

[0015] The rear mounting base is located at the water outlet end of the flow tube. The rear mounting base is equipped with a speed detection unit, a data acquisition and processing unit, a power module, and a signal interface unit. The speed detection unit is used to detect the real-time speed of the shaft. The data acquisition and processing unit is electrically connected to the speed detection unit, the force sensing blade, and the wireless transmission module. It is used to calculate the water flow velocity based on the real-time speed of the shaft and to invert the size of the sediment particles based on the actual impact force signal collected by the force sensing blade.

[0016] The wireless transmission module is used to transmit water flow velocity data and sediment particle size data obtained by the data acquisition and processing unit to an external personal terminal.

[0017] Optionally, the detachable filter assembly includes a filter mounting frame and a filter body. The filter body is fixedly installed inside the filter mounting frame, and the filter mounting frame is detachably connected to the filter insertion slot provided at the water inlet end of the flow cylinder.

[0018] Optionally, the filter body can be configured with different pore sizes, and the filter mounting frame can be pulled out or inserted from the filter insertion slot to achieve replacement of detachable filter assemblies with filter bodies of different pore sizes.

[0019] Optionally, the flow tube can be a cylindrical structure, or a cylindrical structure with an elliptical or polygonal cross-section.

[0020] Optionally, the flow tube is equipped with a rotating shaft support structure, a sensor wiring channel, a detection space, and a depth sensor mounting position. The rotating shaft support structure is used to install and support the rotating shaft, enabling it to rotate around its own axis under the action of water flow. The sensor wiring channel is used to lead the signal line of the force sensing blade to the rear mounting base. The detection space is used to supply water flow to the rotating detection component. The depth sensor mounting position is used to install the depth sensor.

[0021] Optionally, the force sensing blades are in the form of plates or paddles, and are arranged at intervals along the circumference of the rotating shaft, driving the rotating shaft to rotate synchronously.

[0022] Optionally, a sealed connection structure is provided between the flow tube and the rear mounting base to isolate the water flow channel inside the flow tube and the electrical installation space inside the rear mounting base.

[0023] Optionally, the data acquisition and processing unit is used to calculate the water flow velocity based on the pre-calibrated correspondence between the shaft rotation speed and the water flow velocity, and to invert the sediment particle mass based on the actual impact force signal and the current water flow velocity, and further estimate the equivalent particle size of the sediment particles.

[0024] The present invention also provides a detection method using the aforementioned device, comprising the following steps:

[0025] (1) Select a detachable filter assembly with the appropriate aperture according to the aquatic plants, floating objects and silt particles of the river to be tested, and install the detachable filter assembly at the water inlet end of the flow tube.

[0026] (2) Place the device into the river to be tested, so that the inlet end of the flow tube faces the direction of the incoming flow, and the axial direction of the flow tube is consistent with the direction of the main flow, so as to ensure that the water can enter from the inlet end of the flow tube, flow along the water flow channel inside the flow tube, and then be discharged from the outlet end.

[0027] (3) The current deployment depth of the device is obtained by the depth sensor installed in the flow tube, and the depth information is transmitted to an external personal terminal through the wireless transmission module;

[0028] (4) The water flow driving force sensing blades drive the rotating shaft to rotate. After the flow field inside the flow tube reaches a stable state, the rotation speed detection unit collects the rotation speed of the rotating shaft. And transmit the speed signal to the data acquisition and processing unit;

[0029] (5) The data acquisition and processing unit uses the pre-calibrated relational formula. Calculate the current water flow velocity ;

[0030] (6) The mud and sand particles carried in the water flow impact the force sensing blades, and the force sensing blades collect the actual impact force signals. and the actual impact force signal Transmitted to the data acquisition and processing unit;

[0031] (7) The data acquisition and processing unit calculates the current water flow velocity. Determine the foundation stress under the same flow velocity conditions and according to Calculate the additional impact force caused by the impact of sediment particles. ;

[0032] (8) The data acquisition and processing unit is based on the additional impact force Contact time Water flow velocity Impact angle and collision recovery coefficient Estimate the mass of a single sediment particle , And based on the density of sediment particles And further calculate the equivalent particle size of sediment particles using the sphere diameter formula. ;

[0033] (9) The wireless transmission module transmits the water flow rate Equivalent particle size of sediment particles The device deployment depth and corresponding data acquisition time are transmitted to an external personal terminal.

[0034] (10) Adjust the depth of the device in the water body and repeat steps (3) to (9) to obtain the water flow velocity and sediment particle size data at different water depths.

[0035] Furthermore, the detection device is calibrated in a laboratory water tank before actual river testing. The calibration includes the following steps:

[0036] (1) Fix the detection device in the adjustable flow rate water tank, so that the water inlet end of the flow tube faces the direction of the water tank flow, and the axial direction of the flow tube is consistent with the direction of the main flow of the water tank.

[0037] (2) Adjust the flow rate of the water tank and use a standard flow meter to measure the actual flow rate in the water tank;

[0038] (3) Record the rotational speed of the shaft under different actual flow velocities. The flow velocity proportionality coefficient is obtained through fitting. and flow rate correction term and will and Stored in the data acquisition and processing unit;

[0039] (4) Record the foundation forces of the force-sensing blades under different flow velocities without adding sediment particles. And use it as the basic force data for background correction during actual testing;

[0040] (5) Using standard sediment particles of known mass and known particle size, they are placed into the inflow of the water tank, so that they enter the flow tube with the water flow and impact the force sensing blades; the actual impact force signal is recorded by the force sensing unit. and contact time The data acquisition and processing unit is based on the actual impact force signal. Calculate the mass of sediment particles and equivalent particle size The calculation results are then compared with known parameters of standard sediment particles to determine or correct the collision recovery coefficient. Impact angle ;

[0041] (6) The calculated equivalent particle size The particle size was compared with that of standard sediment particles to verify the accuracy of the device in detecting the size of drift sediment particles.

[0042] Beneficial effects: Compared with the prior art, the significant technical effects of the present invention are: (1) The device of the present invention can perform in-situ synchronous measurement of flow velocity and sediment size. The device can accurately measure the river flow velocity and sediment size, and obtain the instantaneous flow velocity and sediment size at full water depth; (2) The device of the present invention has a simple structure, low production cost and is easy to carry and deploy. Attached Figure Description

[0043] Figure 1 This is a schematic diagram of the overall structure of the real-time detection device for river flow velocity and accompanying sediment described in this invention.

[0044] Figure 2 This is a schematic diagram illustrating the data transmission between the real-time river flow velocity and sediment monitoring device of the present invention and an external personal terminal.

[0045] Figure 3 This is a schematic diagram of the exploded structure of the real-time detection device for river flow velocity and accompanying sediment described in this invention;

[0046] Figure 4 This is a schematic diagram of the detachable filter assembly in an embodiment of the present invention;

[0047] Figure 5 This is a schematic diagram of the structure of the rotation detection component in an embodiment of the present invention;

[0048] Figure 6 This is a schematic diagram of the cooperation structure between the filter screen insertion slot and the filter screen mounting frame in an embodiment of the present invention;

[0049] Figure 7 These are schematic diagrams of the structure of filter bodies with different pore sizes in embodiments of the present invention;

[0050] Figure 8 This is a schematic diagram showing the overall structure and installation position of the detachable filter assembly of the real-time detection device for river flow velocity and sediment flow described in this invention.

[0051] The components include: 1. Detachable filter assembly; 2. Rotation detection assembly; 3. Flow cylinder; 4. Rear mounting base; 5. Wireless transmission module; 6. Filter mounting frame; 7. Filter body; 8. Force sensing blades; 9. Rotating shaft; 10. Filter insertion slot. Detailed Implementation

[0052] The present invention will be further described below with reference to the accompanying drawings. It should be noted that the drawings are only for illustrative purposes, illustrating the structural relationships of the present invention, and do not limit the actual dimensions, proportions, or installation methods of the components. For those skilled in the art, any equivalent substitutions or conventional modifications to the shape, size, and connection methods of the structures made without departing from the technical concept of the present invention should be included within the scope of protection of the present invention.

[0053] To address the existing technical problems, there is an urgent need for a low-cost, high-precision technology that can simultaneously monitor flow velocity and sediment size. The requirements are: (1) Non-contact or low-interference design: to avoid sensor clogging or wear and to adapt to high sediment content environments. (2) Multi-parameter synchronous acquisition: to correlate flow velocity and sediment size data in real time to enhance the analytical value. (3) Intelligent and automated: to embed data processing and support wireless transmission and remote monitoring.

[0054] This invention proposes a real-time detection device for river flow velocity and accompanying sediment. Through a force sensor and a flow velocity measuring device, it realizes in-situ synchronous measurement of flow velocity and sediment size, providing an innovative solution for smart water conservancy.

[0055] like Figures 1 to 3 As shown in the figure, this embodiment provides a real-time detection device for river flow velocity and accompanying sediment, including a detachable filter assembly 1, a rotating detection assembly 2, a flow passage cylinder 3, a rear mounting base 4, and a wireless transmission module 5. The detachable filter assembly 1 is located at the inlet end of the flow passage cylinder 3, the rotating detection assembly 2 is located inside the flow passage cylinder 3, the rear mounting base 4 is located at the outlet end of the flow passage cylinder 3, and the wireless transmission module 5 is located outside the rear mounting base 4.

[0056] The detection device described in this invention is mainly used for in-situ synchronous detection of water flow velocity and the size of drift sediment particles in actual river environments. The laboratory water tank environment is mainly used for parameter calibration and verification of detection results before the device is used, including calibration of the relationship between the rotational speed of the rotating shaft in the rotating detection component 2 and the water flow velocity, acquisition of the force data of the foundation of the force sensing blade 8 under different water flow velocities, and determination of the collision recovery coefficient.

[0057] The flow passage cylinder 3 is the main structure of this device, and its overall shape is a cylindrical structure that runs from front to back. The flow passage cylinder 3 is preferably cylindrical, but it can also be configured as a flow passage shell with an elliptical or polygonal cross-section, depending on the actual installation environment. The flow passage cylinder 3 includes an inlet end and an outlet end. The inlet end is used to receive the incoming water flow, and the outlet end is used to discharge the water flow. In use, the inlet end of the flow passage cylinder 3 faces the direction of the actual river flow, allowing the water to enter the interior of the flow passage cylinder 3 from the inlet end, flow axially along the flow passage cylinder 3, and then be discharged from the outlet end.

[0058] The flow passage 3 forms an axially continuous water flow channel inside, allowing river water to flow continuously through the detection device without significant obstruction. The flow passage 3 serves not only as the water flow channel but also as the mounting base for the rotating detection component 2 and related sensing structures. Specifically, the flow passage 3 contains a shaft support structure, a sensor wiring channel, a detection space, and a depth sensor mounting position. The shaft support structure is used to install and support the rotating shaft 9 in the rotating detection component 2, ensuring its rotational stability. The shaft support structure can be a bearing seat or shaft support component mounted on the inner wall of the flow passage 3. The sensor wiring channel is arranged along the inner wall or interlayer of the flow passage 3, used to lay signal lines for components such as the force sensing blade 8 and the depth sensor, and leads the signal lines to the rear mounting base 4. The detection space is located within the water flow channel inside the flow passage 3, ensuring that the water flow can fully act on the rotating detection component 2. The depth sensor mounting position is used to install a depth sensor to detect the deployment depth of the device in the water.

[0059] A sealed connection structure is provided between the flow passage cylinder 3 and the rear mounting base 4. This sealed connection structure is located at the connection between the water outlet end of the flow passage cylinder 3 and the rear mounting base 4. It is used to isolate the water flow channel inside the flow passage cylinder 3 and the electrical installation space inside the rear mounting base 4, and to prevent water from entering the interior of the rear mounting base 4, thereby ensuring the reliability of the operation of the speed detection unit, data acquisition and processing unit, power supply module and signal interface unit.

[0060] like Figure 4 , Figure 6 and Figure 7As shown, the detachable filter assembly 1 is located at the water inlet end of the flow-through cylinder 3 and at the very front of the entire detection device. The detachable filter assembly 1 includes a filter mounting frame 6 and a filter body 7. The outer contour of the filter mounting frame 6 is adapted to the cross-sectional shape of the water inlet end of the flow-through cylinder 3, and the filter mounting frame 6 can be a ring-shaped frame structure. The filter body 7 is fixedly installed within the filter mounting frame 6 and covers the water inlet of the flow-through cylinder 3. A filter insertion groove 10 is provided at the water inlet end of the flow-through cylinder 3, and the filter mounting frame 6 is detachably connected to the filter insertion groove 10. The filter mounting frame 6 can be pulled out or inserted into the filter insertion slot 10 to replace the detachable filter assembly 1 with filter bodies 7 of different pore sizes. In use, the filter mounting frame 6 can be inserted into the filter insertion slot 10 to fix the filter body 7 to the water inlet end of the flow cylinder 3. When it is necessary to replace the detachable filter assembly 1, the filter mounting frame 6 can be pulled out from the filter insertion slot 10.

[0061] The filter body 7 is used to prevent aquatic plants, floating objects, and large debris from entering the flow channel 3, thus preventing these debris from becoming entangled in the rotating shaft 9 or interfering with the normal rotation of the force sensor blades 8. Figure 7 and Figure 8 As shown, the filter body 7 can be configured with different pore sizes. The operator can select the appropriate pore size of the filter body 7 according to the size of floating objects, the range of silt particles, and the on-site testing requirements in the actual river. By replacing the detachable filter assembly 1, the size of solid materials entering the flow passage cylinder 3 can be pre-screened to prevent aquatic plants and large debris from entering the device and entangled in the rotating detection assembly 2.

[0062] like Figure 5 As shown, the rotating detection component 2 is disposed inside the flow passage cylinder 3 and located downstream of the detachable filter assembly 1. The rotating detection component 2 includes a rotating shaft 9 and force sensing blades 8. The rotating shaft 9 is arranged laterally inside the flow passage cylinder 3 (i.e., the rotating shaft 9 is arranged radially or approximately radially along the flow passage cylinder 3), and its two ends are respectively mounted on the opposite inner walls of the flow passage cylinder 3 through bearings or rotating shaft supports, so that the rotating shaft 9 can rotate around its own axis under the action of water flow. The force sensing blades 8 are fixedly disposed on the rotating shaft 9 and are arranged at intervals around the circumference of the rotating shaft 9, and the force sensing blades 8 drive the shaft 9 to rotate synchronously. The force sensing blades 8 can be plate-shaped or paddle-shaped structures, and force sensing units are provided inside or on the surface of the blades to detect the actual impact force signal generated when sediment particles collide with the sensing blades 8.

[0063] After entering the flow channel 3, the water first passes through the detachable filter assembly 1 and then acts on the rotation detection assembly 2. The water flow drives the force sensing blades 8 to rotate, and the force sensing blades 8 drive the rotating shaft 9 to rotate synchronously; at the same time, the sediment particles carried in the water flow impact the force sensing blades 8, generating actual impact force signals. Thus, the rotation detection assembly 2 can simultaneously obtain the rotational speed signal related to the water flow velocity and the force signal related to the impact of sediment particles during the same water flow process.

[0064] The rear mounting base 4 is located at the outlet end of the flow-through cylinder 3 and is fixedly connected to the flow-through cylinder 3. The rear mounting base 4 can be a cylindrical structure with internal installation space, which houses a speed detection unit, a data acquisition and processing unit, a power supply module, and a signal interface unit. The speed detection unit works with the rotating shaft 9 via magnetic induction, photoelectric induction, or an encoder to detect the real-time speed of the rotating shaft 9. The data acquisition and processing unit is electrically connected to the speed detection unit, the force sensing unit on the force sensing blade 8, the depth sensor, and the wireless transmission module 5, respectively, to receive and process speed, force, and depth signals. The power supply module supplies power to the speed detection unit, the data acquisition and processing unit, the force sensing unit on the force sensing blade 8, the depth sensor, and the wireless transmission module 5. The signal interface unit connects the signal lines of the sensors inside the flow-through cylinder 3 to the data acquisition and processing unit.

[0065] The wireless transmission module 5 is located on the outside of the rear mounting base 4 or within the sealed cavity of the rear mounting base 4, and is electrically connected to the data acquisition and processing unit. The wireless transmission module 5 transmits the water flow velocity data, sediment particle impact signals, sediment particle size data, device deployment depth data, and acquisition time obtained by the data acquisition and processing unit to an external personal terminal. The external personal terminal can be a computer, tablet computer, or mobile terminal, used for displaying, storing, and exporting the detection data. The external personal terminal is not part of the internal structure of the flow tube 3; it only serves as a receiving and display device for the detection data.

[0066] The working principle of this device is as follows: During actual river monitoring, the inlet end of the flow passage cylinder 3 is oriented towards the incoming water flow, allowing the water to enter the flow passage cylinder 3 through the detachable filter assembly 1. The detachable filter assembly 1 blocks aquatic plants and large floating objects, and the filtered water enters the flow passage cylinder 3 and acts on the force sensing blades 8. Under the action of the water flow, the force sensing blades 8 drive the rotating shaft 9 to rotate. The rotation speed detection unit in the rear mounting base 4 collects the real-time rotation speed of the rotating shaft 9, and the data acquisition and processing unit calculates the water flow velocity based on the pre-calibrated correspondence between the rotating shaft rotation speed and the water flow velocity. At the same time, the flowing sediment particles impact the force sensing blades 8, and the force sensor on the force sensing blades 8 collects the actual impact force signal. The data acquisition and processing unit inverts the mass of the sediment particles based on the actual impact force signal and the current water flow velocity, and further estimates the equivalent particle size of the sediment particles. Since both the rotation speed signal and the actual impact force signal are obtained by the rotating detection component 2 inside the same flow tube 3 during the same water flow process, the water flow velocity data and the sediment particle impact data have a corresponding relationship in terms of acquisition time and spatial location. This can reduce the time and spatial misalignment caused by the traditional separate measurement method and realize in-situ synchronous detection of water flow velocity and the size of the flowing sediment particles.

[0067] Before use, this device can be calibrated in an experimental water tank to obtain the flow velocity proportionality coefficient and correction parameters, and to establish the blade force baseline distribution data under different flow velocity conditions for subsequent sediment particle detection correction. Specifically, the device is placed in an adjustable flow velocity water tank with a known flow velocity, the flow velocity of the water tank is changed, and the rotational speed of the shaft 9 is recorded under different flow velocity conditions. The water flow velocity is obtained by fitting the flow velocity and rotation speed data. With shaft speed The correspondence between them. In this embodiment, the correspondence can be expressed as:

[0068] (1)

[0069] in, For water flow velocity, The rotational speed of the shaft. This is the flow velocity proportionality coefficient. This is a flow rate correction term. and The data was obtained through calibration in an experimental water tank and pre-stored in the data acquisition and processing unit within the rear mounting base 4. During actual river testing, the rotational speed detection unit collects the rotational speed of the shaft 9 in real time. The data acquisition and processing unit calculates the current water flow velocity based on the above correspondence. .

[0070] During the flow of water through the flow channel 3, the force-sensing blades 8 experience inherent stress under the influence of the water flow. To eliminate the impact of the water flow background on the identification of sediment particle impact force, the data acquisition and processing unit can pre-store the inherent stress data of the force-sensing blades 8 under different flow velocities. In actual testing, the actual impact force signal acquired by the force-sensing blades 8 is recorded as follows: Under the same flow velocity conditions, the foundation force of the force-sensing blade 8 is denoted as... The additional impact force caused by the collision of sediment particles is denoted as ,but It can be represented as:

[0071] (2)

[0072] in, The actual impact force signal collected by the force-sensing blade 8. For the basic forces acting on the force-sensing blade 8 under the same flow velocity conditions, The additional impact force caused by the impact force sensing blade 8 of the mud and sand particles.

[0073] In this embodiment, the collision process between the sediment particles and the force-sensing blade 8 can be considered as a partially inelastic collision process. Let the mass of a single sediment particle be... The velocity of the silt particle impact force sensing blade at time 8 is approximately taken as the current water flow velocity. The angle between the direction of sediment particle movement and the normal direction of the force sensing blade is The collision recovery coefficient is The contact time between the sediment particles and the force-sensing blade 8 is When the impact force sensing blade for sediment particles is 8, its incident normal momentum can be expressed as: The normal momentum after the rebound can be expressed as: Based on the relationship of normal momentum change, the additional impact force generated by the mud and sand particle impact force sensing blade at time 8. It can be represented as:

[0074] (3)

[0075] in, Mass of a single sediment particle. For water flow velocity, The impact angle represents the angle between the direction of the sediment particle's movement and the normal direction of the force-sensing blade 8. The collision recovery coefficient is... The contact time between the sediment particles and the force-sensing blade 8.

[0076] In the actual testing process, the force sensing unit installed on the force sensing blade 8 collects the actual impact force signal generated by the impact of sediment particles in real time. The data acquisition and processing unit retrieves the foundation force data corresponding to the same flow velocity condition according to the current water flow velocity, and calculates the additional impact force generated by the impact of sediment particles based on the actual impact force signal and the foundation force data. Since this additional impact force corresponds to the theoretical additional impact force in equation (3), the calculated additional impact force can be substituted into equation (3) to further estimate the mass of a single sediment particle. Its expression is:

[0077] (4)

[0078] Furthermore, the water flow velocity With shaft speed Substituting the correspondence between them into formula (4), we can obtain the mass estimation relationship of sediment particles based on the shaft rotation speed signal and sediment impact force signal:

[0079] (5)

[0080] in, The contact time between the sediment particles and the force-sensing blade 8. For the impact angle, This refers to the collision recovery coefficient. The impact angle can be obtained through a calibrated collision experiment with particles of known mass; The initial value is determined based on the installation angle of the force-sensing blade 8 and the direction of water flow, and then corrected using a standard sediment particle calibration experiment; The duration of the actual impact force signal collected by the force sensing blade 8 can be determined.

[0081] In obtaining the mass of a single sediment particle Subsequently, the data acquisition and processing unit can further analyze the sediment particle density. The relationship between particle size and particle volume is used to estimate sediment particle size. When sediment particles are approximately considered spherical, their equivalent particle size... It can be represented as:

[0082] (6)

[0083] in, The equivalent particle size of the sediment particles. The density of the sediment particles is given. Therefore, the data acquisition and processing unit can obtain information on the water flow velocity and the size of the sediment particles flowing with the current based on the rotational speed signal of the shaft 9, the actual impact force signal of the force-sensing blade 8, and pre-calibrated parameters.

[0084] To reduce the impact of water flow disturbance, electrical signal noise, and non-sediment particle collisions on the detection results, the data acquisition and processing unit can perform threshold filtering and time filtering on the actual impact force signals collected by the force sensing blade 8. When the force signal amplitude is lower than a preset threshold, or the force signal duration is less than a preset time threshold, the signal can be identified as a background disturbance signal and discarded. The filtered effective impact force signals are used for estimating the mass and equivalent particle size of sediment particles.

[0085] A practical river detection method using the aforementioned real-time river flow velocity and sediment detection device includes the following steps:

[0086] (1) Based on the condition of aquatic plants, floating objects and silt particles in the river to be tested, select a detachable filter assembly 1 with the appropriate aperture, and then insert the filter mounting frame 6 into the filter insertion groove 10 at the water inlet end of the flow tube 3 so that the detachable filter assembly 1 is installed at the water inlet end of the flow tube 3.

[0087] (2) Place the device into the river to be tested, so that the inlet end of the flow tube 3 faces the direction of the incoming flow, and the axial direction of the flow tube 3 is basically consistent with the direction of the main flow, so as to ensure that the water can enter from the inlet end of the flow tube 3, flow along the water flow channel inside the flow tube 3 and be discharged from the outlet end.

[0088] (3) The current deployment depth of the device is obtained by the depth sensor installed in the flow tube 3, and the depth information is transmitted to an external personal terminal through the wireless transmission module 5.

[0089] (4) The water flow driving force sensing blade 8 drives the rotating shaft 9 to rotate. After the flow field inside the flow tube 3 reaches a stable state, the rotation speed detection unit collects the rotation speed of the rotating shaft 9. And transmit the speed signal to the data acquisition and processing unit;

[0090] (5) The data acquisition and processing unit uses the pre-calibrated relational formula. Calculate the current water flow velocity ;

[0091] (6) The force sensing blade 8 is formed by the impact of sediment particles carried in the water flow, and the force sensing blade 8 collects the actual impact force signal. and the actual impact force signal Transmitted to the data acquisition and processing unit;

[0092] (7) The data acquisition and processing unit calculates the current water flow velocity. Determine the foundation stress under the same flow velocity conditions and according to Calculate the additional impact force caused by the impact of sediment particles. ;

[0093] (8) The data acquisition and processing unit is based on the additional impact force Contact time Water flow velocity Impact angle and collision recovery coefficient Estimate the mass of a single sediment particle And based on the density of sediment particles Further calculation of the equivalent particle size of sediment particles ;

[0094] (9) The wireless transmission module 5 transmits the water flow rate Equivalent particle size of sediment particles The device deployment depth and corresponding data acquisition time are transmitted to an external personal terminal.

[0095] (10) Adjust the depth of the device in the water body and repeat steps (3) to (9) to obtain the water flow velocity and sediment particle size data at different water depths.

[0096] This invention should also be calibrated and verified in a laboratory water bath environment. The laboratory calibration and verification process includes the following steps:

[0097] (1) Fix the detection device in the adjustable flow rate water tank, so that the water inlet end of the flow tube 3 faces the direction of the water tank flow, and make the axial direction of the flow tube 3 basically consistent with the direction of the main flow of the water tank.

[0098] (2) Adjust the flow rate of the water tank and use a standard flow meter to measure the actual flow rate in the water tank;

[0099] (3) Record the rotational speed of shaft 9 under different actual flow velocities. The flow velocity proportionality coefficient is obtained through fitting. and flow rate correction term and will and Stored in the data acquisition and processing unit;

[0100] (4) Record the foundation forces of the force-sensing blade 8 under different flow velocities without adding sediment particles. And use it as the basic force data for background correction during actual testing;

[0101] (5) Using standard sediment particles of known mass and known particle size, they are placed into the incoming flow of the water tank, so that they enter the flow tube 3 with the water flow and impact the force sensing blades 8; the actual impact force signal is recorded by the force sensing unit. and contact time The data acquisition and processing unit is based on the actual impact force signal. Calculate the mass of sediment particles and equivalent particle size The calculation results are then compared with known parameters of standard sediment particles to determine or correct the collision recovery coefficient. Impact angle .

[0102] (6) The calculated equivalent particle size The particle size was compared with that of standard sediment particles to verify the accuracy of the device in detecting the size of drift sediment particles.

[0103] Through the aforementioned structure and detection method, this device can achieve synchronous in-situ detection of water flow velocity and the size of drift sediment particles in actual rivers. The detachable filter assembly 1 reduces interference from aquatic plants and large debris on the rotating detection assembly 2; the flow passage cylinder 3 provides a stable structural foundation for water flow, installation of the rotating detection assembly 2, and sensor wiring; the rear mounting base 4 provides sealed protection for the rotation speed detection unit, data acquisition and processing unit, power module, and signal interface unit; and the wireless transmission module 5 transmits the detection results to an external personal terminal in real time, thereby improving the synchronization, real-time performance, and field applicability of river flow velocity and drift sediment particle size detection.

[0104] Obviously, the above embodiments are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. Those skilled in the art will recognize that other variations or modifications can be made based on the above description and ideas; it is neither necessary nor possible to exhaustively list all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A real-time detection device for river flow velocity and accompanying sediment, characterized in that, It includes a detachable filter assembly (1), a rotation detection assembly (2), a flow cylinder (3), a rear mounting base (4), and a wireless transmission module (5); The flow tube (3) is a cylindrical structure that runs through the front and back, including an inlet end and an outlet end. A water flow channel that runs through the axial direction is formed inside the flow tube. A detachable filter assembly (1) is installed at the water inlet end of the flow tube to prevent debris from entering the interior of the flow tube; The rotating detection component (2) is located inside the flow tube and downstream of the detachable filter assembly. The rotating detection component includes a rotating shaft (9) and a force sensing blade (8) on the rotating shaft. The force sensing blade is used to drive the rotating shaft to rotate under the action of water flow and to collect the actual impact force signal generated when the mud and sand particles hit the force sensing blade. The rear mounting base (4) is set at the water outlet end of the flow tube. The rear mounting base is equipped with a speed detection unit, a data acquisition and processing unit, a power module and a signal interface unit. The speed detection unit is used to detect the real-time speed of the shaft. The data acquisition and processing unit is electrically connected to the speed detection unit, the force sensing blade and the wireless transmission module respectively. It is used to calculate the water flow velocity based on the real-time speed of the shaft and to invert the size of the sediment particles based on the actual impact force signal collected by the force sensing blade. The wireless transmission module (5) is used to transmit the water flow velocity data and sediment particle size data obtained by the data acquisition and processing unit to an external personal terminal.

2. The apparatus according to claim 1, characterized in that, The detachable filter assembly (1) includes a filter mounting frame (6) and a filter body (7). The filter body is fixedly installed in the filter mounting frame, and the filter mounting frame is detachably connected to the filter insertion slot provided at the water inlet end of the flow cylinder.

3. The apparatus according to claim 2, characterized in that, The filter body (7) is set with different pore sizes, and the filter mounting frame (6) can be pulled out or inserted into the filter insertion slot (10) to realize the replacement of the detachable filter assembly with filter bodies of different pore sizes.

4. The apparatus according to claim 1, characterized in that, The flow tube (3) is a cylindrical structure, or a cylindrical structure with an elliptical or polygonal cross-section.

5. The apparatus according to claim 1, characterized in that, The flow tube (3) is equipped with a rotating shaft support structure, a sensor wiring channel, a detection space and a depth sensor mounting position. The rotating shaft support structure is used to install and support the rotating shaft so that the rotating shaft can rotate around its own axis under the action of water flow. The sensor wiring channel is used to lead the signal line of the force sensing blade to the rear mounting base. The detection space is used to supply water flow to the rotating detection component. The depth sensor mounting position is used to install the depth sensor.

6. The apparatus according to claim 1, characterized in that, The force sensing blades (8) are in the form of a plate or a paddle. The force sensing blades are arranged at intervals along the circumference of the rotating shaft and drive the rotating shaft to rotate synchronously.

7. The apparatus according to claim 1, characterized in that, A sealed connection structure is provided between the flow tube and the rear mounting base to isolate the water flow channel inside the flow tube and the electrical installation space inside the rear mounting base.

8. The apparatus according to claim 1, characterized in that, The data acquisition and processing unit is used to calculate the water flow velocity based on the pre-calibrated correspondence between the shaft rotation speed and the water flow velocity, and to invert the sediment particle mass based on the actual impact force signal and the current water flow velocity, and further estimate the equivalent particle size of the sediment particles.

9. A detection method using the apparatus according to any one of claims 1 to 8, characterized in that, Includes the following steps: (1) Select a detachable filter assembly with the appropriate aperture according to the aquatic plants, floating objects and silt particles of the river to be tested, and install the detachable filter assembly at the water inlet end of the flow tube. (2) Place the device into the river to be tested, so that the inlet end of the flow tube faces the direction of the incoming flow, and the axial direction of the flow tube is consistent with the direction of the main flow, so as to ensure that the water can enter from the inlet end of the flow tube, flow along the water flow channel inside the flow tube, and then be discharged from the outlet end. (3) The current deployment depth of the device is obtained by the depth sensor installed in the flow tube, and the depth information is transmitted to an external personal terminal through the wireless transmission module; (4) The water flow driving force sensing blades drive the rotating shaft to rotate. After the flow field inside the flow tube reaches a stable state, the rotation speed detection unit collects the rotation speed of the rotating shaft. And transmit the speed signal to the data acquisition and processing unit; (5) The data acquisition and processing unit uses the pre-calibrated relational formula. Calculate the current water flow velocity ; (6) The mud and sand particles carried in the water flow impact the force sensing blades, and the force sensing blades collect the actual impact force signals. and the actual impact force signal Transmitted to the data acquisition and processing unit; (7) The data acquisition and processing unit calculates the current water flow velocity. Determine the foundation stress under the same flow velocity conditions and according to Calculate the additional impact force caused by the impact of sediment particles. ; (8) The data acquisition and processing unit is based on the additional impact force Contact time Water flow velocity Impact angle and collision recovery coefficient Estimate the mass of a single sediment particle , And based on the density of sediment particles And further calculate the equivalent particle size of sediment particles using the sphere diameter formula. ; (9) The wireless transmission module transmits the water flow rate Equivalent particle size of sediment particles The device deployment depth and corresponding data acquisition time are transmitted to an external personal terminal. (10) Adjust the depth of the device in the water body and repeat steps (3) to (9) to obtain the water flow velocity and sediment particle size data at different water depths.

10. The detection method according to claim 9, characterized in that, The detection device is calibrated in a laboratory water tank before actual river testing. The calibration includes the following steps: (1) Fix the detection device in the adjustable flow rate water tank, so that the water inlet end of the flow tube faces the direction of the water tank flow, and the axial direction of the flow tube is consistent with the direction of the main flow of the water tank. (2) Adjust the flow rate of the water tank and use a standard flow meter to measure the actual flow rate in the water tank; (3) Record the rotational speed of the shaft under different actual flow velocities. The flow velocity proportionality coefficient is obtained through fitting. and flow rate correction term and will and Stored in the data acquisition and processing unit; (4) Record the foundation forces of the force-sensing blades under different flow velocities without adding sediment particles. And use it as the basic force data for background correction during actual testing; (5) Using standard sediment particles of known mass and known particle size, they are placed into the inflow of the water tank, so that they enter the flow tube with the water flow and impact the force sensing blades; the actual impact force signal is recorded by the force sensing unit. and contact time The data acquisition and processing unit is based on the actual impact force signal. Calculate the mass of sediment particles and equivalent particle size The calculation results are then compared with known parameters of standard sediment particles to determine or correct the collision recovery coefficient. Impact angle ; (6) The calculated equivalent particle size The particle size was compared with that of standard sediment particles to verify the accuracy of the device in detecting the size of drift sediment particles.

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