Multi-distance layered anti-interference open channel flow measuring device and flow measuring method

Abstract

The multi-distance layered anti-interference open channel flow measuring device comprises canal side walls (1) and a canal bottom (2), and is characterized in that a plurality of strip-shaped notches (3) are formed in the surfaces of the two opposite inner side walls of the canal side walls (1) in the longitudinal direction, at least two strip-shaped notches (3) which are spaced by a certain distance are formed in the canal side wall (1) located on one side, and the two strip-shaped notches (3) are formed in the canal bottom (2) in the longitudinal direction. Pre-embedded mounting bases (4) are fixedly arranged in the strip-shaped notches (3) respectively, the side, close to a ditch water body, of each arc-shaped inserting groove (7) is arranged to be an open face, flow measuring units are installed in the arc-shaped inserting grooves (7) respectively, and a plurality of flow measuring sensors (16) are installed in the flow measuring units at intervals along different water level heights. The device can adapt to long-time outdoor real-time detection, the influence of water temperature on the detection progress is avoided, the influence of main factors such as machinery and time delay on flow velocity measurement is reduced, and the measurement precision is remarkably improved.

Description

Technical Field

[0001] The invention relates to an open channel flow measurement device and a flow measurement method, in particular to a multi-distance layered anti-interference open channel flow measurement device and a flow measurement method, belonging to the technical field of hydrological flow measurement. Background Art

[0002] my country is a large agricultural country. Most of the water resources in the total water consumption are used for agricultural irrigation. Water shortage has seriously hindered the development of modern agriculture in my country. In order to better realize water measurement in irrigation areas, the best way is to combine scientific measurement and precise monitoring, improve the level of information construction in irrigation areas, make scientific and rational use of water resources, and reduce water waste. The research time of water measurement technology in irrigation areas in my country is relatively short, so there are still many problems in the practical application of open channel flow measurement. There are many types of flow measurement equipment. The existing flow measurement equipment is mainly based on flow velocity meters with high flow measurement accuracy, but most of them are expensive and have low automation, and cannot realize long-term data monitoring. In particular, water measurement equipment with weirs, troughs, canals, etc. as the main objects has a relatively harsh outdoor natural environment. The flow measurement equipment has the problem of difficult installation, and it is easy to age and deform during use. These unfavorable factors are not conducive to the modernization of agricultural irrigation areas.

[0003] In addition, although there are many methods for measuring flow in open channels, they all have their own limitations and cannot meet the current requirements for water measuring equipment. For example, various factors such as measurement accuracy, convenience, and cost more or less cannot meet the measurement needs. The existing flow measuring equipment has a low flow measurement progress. The water temperature and the flow velocity of water in different water layers in the irrigation canal will affect the detection accuracy. For example, due to the geometric characteristics of the canal, the water flow velocity at the bottom, middle and top of the canal is different. Especially in the case of a large amount of sediment, bubbles, turbulence, etc., the detection accuracy is greatly reduced. For a long time, how to accurately measure the flow and reduce interference factors has been a common technical problem in this field. There has always been a lack of a scientific and reasonable flow measurement method to solve the above technical problems. Summary of the invention

[0004] The first purpose of the present invention is to address the defects and shortcomings of existing water channel flow measuring devices, such as the difficulty of outdoor open channel installation, the proneness to aging and deformation during use in outdoor natural environments, the inability to achieve long-term real-time monitoring, and the high price. The present application provides a multi-distance layered anti-interference open channel flow measuring device with a reasonable structure, low cost, easy installation, improved anti-interference and anti-aging properties, and capable of achieving long-term real-time monitoring.

[0005] The second purpose of the present invention is to address the defects and shortcomings of existing outdoor open channel methods, such as poor accuracy, being greatly affected by factors such as water temperature, sediment, bubbles, turbulence, etc., and having different flow velocities in water layers at different depths in the channel, making it impossible to achieve relatively accurate measurement. The present application provides a multi-distance layered anti-interference open channel flow measurement device with a reasonable algorithm and fast processing speed, which can adapt to long-term outdoor real-time detection, avoids the influence of water temperature on the detection progress, reduces the influence of major factors such as machinery and time delay on the measurement of flow velocity, and significantly improves the measurement accuracy.

[0006] To achieve the above-mentioned first invention purpose, the technical solution of the present invention is: a multi-distance layered anti-interference open channel flow measuring device, including a channel side wall and a channel bottom, wherein the two inner wall surfaces opposite to each other of the channel side wall are respectively provided with a plurality of strip-shaped grooves along the longitudinal direction, wherein at least two strip-shaped grooves spaced at a certain interval are provided on the channel side wall on one side, and embedded mounting seats are respectively fixedly arranged in the strip-shaped grooves, and the side of the arc-shaped plug-in groove close to the ditch water body is set as an open surface, and flow measuring units are respectively installed in the arc-shaped plug-in grooves, and a plurality of flow measuring sensors are installed in the flow measuring unit along different water level heights.

[0007] Furthermore, two strip-shaped slots are opened on the inner wall of one side of the canal side wall at a certain interval, and a No. 1 flow measuring unit is installed in one of the strip-shaped slots, and a No. 2 flow measuring unit is installed in the other strip-shaped slot. A strip-shaped slot is opened on the inner wall on the other side of the canal side wall, and a No. 3 flow measuring unit is installed in the strip-shaped slot. The No. 3 flow measuring unit is respectively arranged to correspond to the No. 1 flow measuring unit and the No. 2 flow measuring unit.

[0008] Furthermore, the embedded mounting seat includes a bottom plate surface, an outer arc surface and an arc-shaped plug-in groove. The bottom plate surface is located on the inner side of the strip-shaped groove. The outer arc surfaces are symmetrically fixed on both sides of the bottom plate surface, and an arc-shaped plug-in groove is arranged between the two outer arc surfaces.

[0009] Furthermore, the flow measuring unit includes a curved sensor housing, a sensor mounting cavity, an end seal and a plurality of flow measuring sensors. The curved sensor housing is a long strip-shaped cavity structure with one end open. A sensor mounting cavity is provided inside the curved sensor housing, and the open end of the curved sensor housing is sealed by an end seal.

[0010] Furthermore, a plurality of sensor detection holes are provided on the outer wall of the arc sensor housing corresponding to the open surface of the arc-shaped plug-in slot, a flow measuring sensor is installed in the sensor installation cavity, and the detection end of the flow measuring sensor is located in the sensor detection hole.

[0011] Furthermore, a sensor clamping and fixing groove corresponding to the sensor detection hole is provided on the inner wall of the sensor installation cavity, and a flow measuring sensor is fixed on the sensor clamping and fixing groove.

[0012] Furthermore, the flow measuring sensor is an ultrasonic transducer or a radar flow measuring sensor.

[0013] To achieve the second object of the present invention, the technical solution of the present invention is: a flow measurement method using a multi-distance layered anti-interference open channel flow measurement device, comprising the following steps:

[0014] A. First, connect three or more flow measuring units, check the waterproof sealing, and establish electrical connections between the flow measuring units and the controllers on the bank of the canal;

[0015] B. Then, the flow measuring units are inserted and installed in the pre-buried mounting bases one by one, and the angles of the flow measuring units are adjusted according to the detection requirements of the flow measuring sensors to meet the requirements of the two-to-two cross-reflection of multiple flow measuring units;

[0016] C. Then, the distance parameter L of the device is measured by the flow measuring unit in the air without flowing water between the flow measuring units on both sides;

[0017] D. The attitude sensor integrated in the flow measurement unit is used to obtain the attitude difference of the measuring point, and the specific 3D coordinate position of the detection signal or detection wave transceiver of each flow measurement sensor for different depths is solved through 3D attitude analysis, and the precise distance between the flow measurement sensors at each measuring point in the flow measurement unit is further obtained;

[0018] E. Since the flow velocity of each layer in the open channel is quite different, the flow velocity of each water layer Vi is obtained by layered measurement, i∈M, and the water layers are numbered from top to bottom;

[0019] F. Then, the sound velocity elimination algorithm is used to weaken the influence of the sound velocity in the measurement, so as to avoid the serious influence of the sound velocity in the presence of sediment, which will cause excessive measurement errors.

[0020] G. Finally, the distance K of the flow sensor on the split measuring device and the attitude quaternion data P of the transceiver are

[0021] The area of ​​the water layer Si = f(L,K,P) is calculated from (w,x,y,z). A relatively accurate cumulative flow rate can be calculated based on the sampling interval ΔT and the total metering time T.

[0022] Furthermore, the sound speed elimination algorithm in step F is as follows:

[0023] When ultrasonic waves are incident from probe A, and received by probe B, the following relationship exists:

[0024]

[0025] When ultrasonic waves are incident from probe B, the following relationship holds when ultrasonic waves are received by probe A:

[0026]

[0027] Subtracting the above two equations, we get:

[0028]

[0029] It can be seen that the expression of flow velocity v no longer contains the ultrasonic wave velocity c.

[0030] Furthermore, the algorithm formula in step G is:

[0031]

[0032] Where ΔQj is the flow rate at any time, V a is the average flow velocity at any time.

[0033] The beneficial effects of the present invention are:

[0034] 1. The present invention opens a strip-shaped groove on the surface of the existing water channel and installs a pre-embedded mounting seat, or the pre-embedded mounting seat is directly embedded, which provides convenience for installing a modular sensor device, and the pre-embedded mounting seat can play a good protective role on the sensor housing, is less affected by external factors such as mud, debris, and exposure, is not easy to deform, and has good anti-aging performance.

[0035] 2. The present invention adopts multiple groups of flow measuring units, which are convenient for installation and angle adjustment, and have strong anti-interference ability. Through the attitude sensor integrated in the flow measuring unit, the attitude difference of the measuring point can be accurately obtained, and the specific 3D coordinate position of the detection signal or detection wave transceiver for different depths in each flow measuring sensor can be calculated through 3D attitude analysis, and the precise distance between the flow measuring sensors at each measuring point in the flow measuring unit can be further obtained.

[0036] 3. The present invention builds an ultrasonic cross-sectional flow velocity measurement model and a flow measurement noise reduction model, and incorporates an intelligent algorithm for flow velocity-area water measurement. The sound velocity elimination algorithm avoids the influence of water temperature on the detection progress. At the same time, it also reduces the influence of major factors such as machinery and time delay on flow velocity measurement, and the measurement accuracy is significantly improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 It is a schematic diagram of the cross-sectional structure of the water channel installed in the present invention.

[0038] Figure 2 It is a schematic diagram of the embedded mounting base of the present invention being installed on a water channel.

[0039] Figure 3 It is a structural schematic diagram of the embedded mounting seat of the present invention.

[0040] Figure 4It is a structural schematic diagram of the first embodiment of the arc sensor housing of the present invention.

[0041] Figure 5 It is a structural schematic diagram of the arc surface sensor housing of the present invention.

[0042] Figure 6 It is a schematic diagram of the internal structure of the arc sensor housing of the present invention.

[0043] Figure 7 It is a schematic diagram of the first embodiment of the arc surface sensor housing of the present invention installed on the embedded mounting seat.

[0044] Figure 8 It is a structural schematic diagram of a second embodiment of the arc surface sensor housing of the present invention.

[0045] Fig. 9 It is a schematic diagram of the second embodiment of the arc surface sensor housing of the present invention installed on the embedded mounting seat.

[0046] Fig.10 It is a schematic diagram of the measurement principle of the present invention. Fig.11 It is a schematic diagram of the measurement principle of multiple measurement points of the present invention.

[0047] In the figure: canal side wall 1, canal bottom 2, strip notch 3, embedded mounting seat 4, bottom plate surface 5, outer arc surface 6, arc plug-in groove 7, No. 1 flow measuring unit 8, No. 2 flow measuring unit 9, No. 3 flow measuring unit 10, arc surface sensor housing 11, sensor mounting cavity 12, end seal 13, sensor detection hole 14, sensor clamping fixing groove 15, flow measuring sensor 16, adjustable toothed disc 17, fixing ring 18. DETAILED DESCRIPTION

[0048] The present invention is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0049] See also Figures 1 to 11 A multi-distance layered anti-interference open channel flow measuring device of the present invention comprises a channel side wall 1 and a channel bottom 2, and is characterized in that: the two inner side wall surfaces opposite to each other of the channel side wall 1 are respectively provided with a plurality of strip-shaped slots 3 along the longitudinal direction, wherein at least two strip-shaped slots 3 with a certain interval are provided on the channel side wall 1 on one side, and embedded mounting seats 4 are respectively fixedly arranged in the strip-shaped slots 3, and the side of the arc-shaped plug-in groove 7 close to the ditch water body is set as an open surface, and flow measuring units are respectively installed in the arc-shaped plug-in groove 7, and a plurality of flow measuring sensors 16 are installed in the flow measuring unit along different water level height intervals.

[0050] Two strip-shaped slots 3 are provided on the inner wall of one side of the canal side wall 1 at a certain interval, wherein a No. 1 flow measuring unit 8 is installed in one of the strip-shaped slots 3, and a No. 2 flow measuring unit 9 is installed in the other strip-shaped slot 3. A strip-shaped slot 3 is provided on the inner wall of the other side of the canal side wall 1, and a No. 3 flow measuring unit 10 is installed in the strip-shaped slot 3. The No. 3 flow measuring unit 10 is respectively arranged corresponding to the No. 1 flow measuring unit 8 and the No. 2 flow measuring unit 9.

[0051] The embedded mounting seat 4 includes a bottom plate surface 5, an outer arc surface 6 and an arc-shaped plug-in groove 7. The bottom plate surface 5 is located on the inner side of the strip-shaped groove 3. The outer arc surfaces 6 are symmetrically fixed on both sides of the bottom plate surface 5, and an arc-shaped plug-in groove 7 is provided between the two outer arc surfaces 6.

[0052] The flow measuring unit includes a curved sensor housing 11, a sensor mounting cavity 12, an end seal 13 and a plurality of flow measuring sensors 16. The curved sensor housing 11 is a long strip-shaped cavity structure with one end open. The interior of the curved sensor housing 11 is provided with a sensor mounting cavity 12. The open end of the curved sensor housing 8 is sealed by an end seal 13.

[0053] The outer wall of the arc sensor housing 11 is provided with a plurality of sensor detection holes 14 corresponding to the open surface of the arc plug-in slot 7 . A flow measuring sensor 16 is installed in the sensor installation cavity 12 , and the detection end of the flow measuring sensor 16 is located in the sensor detection hole 14 .

[0054] An adjustable toothed disc 17 is fixedly disposed on the upper end of the arc sensor housing 11 , and a fixing ring 18 with a toothed ring is fixedly disposed on the upper end of the arc-shaped plug-in slot 7 . The toothed ring on the fixing ring 18 matches the tooth structure on the adjustable toothed disc 17 .

[0055] A sensor clamping and fixing groove 15 corresponding to the sensor detection hole 14 is arranged on the inner wall of the sensor installation cavity 12 , and a flow measuring sensor 16 is fixed on the sensor clamping and fixing groove 15 .

[0056] The flow measuring sensor 16 is an ultrasonic transducer or a radar flow measuring sensor.

[0057] A flow measurement method using a multi-distance layered anti-interference open channel flow measurement device comprises the following steps:

[0058] A. First, connect three or more flow measuring units, check the waterproof sealing, and establish electrical connections between the flow measuring units and the controllers on the bank of the canal;

[0059] B. Then, the flow measuring units are inserted and installed in the pre-buried mounting bases one by one, and the angles of the flow measuring units are adjusted according to the detection requirements of the flow measuring sensors to meet the requirements of the two-to-two cross-reflection of multiple flow measuring units;

[0060] C. Then, the distance parameter L of the device is measured by the flow measuring unit in the air without flowing water between the flow measuring units on both sides;

[0061] D. The attitude sensor integrated in the flow measurement unit is used to obtain the attitude difference of the measuring point, and the specific 3D coordinate position of the detection signal or detection wave transceiver of each flow measurement sensor for different depths is solved through 3D attitude analysis, and the precise distance between the flow measurement sensors at each measuring point in the flow measurement unit is further obtained;

[0062] E. Since the flow velocity of each layer in the open channel is quite different, the flow velocity of each water layer Vi is obtained by layered measurement, i∈M, and the water layers are numbered from top to bottom;

[0063] F. Then, the sound velocity elimination algorithm is used to weaken the influence of the sound velocity in the measurement, so as to avoid the serious influence of the sound velocity in the presence of sediment, which will cause excessive measurement errors.

[0064] G. Finally, the area of ​​the water layer Si = f (L, K, P) is calculated through the spacing K of the flow measuring sensors on the split measuring device and the attitude quaternion data P (w, x, y, z) of the transceiver equipment. The relatively accurate cumulative flow rate can be calculated based on the sampling interval ΔT and the total metering time T.

[0065] The specific algorithm for eliminating the sound speed term in step F is as follows:

[0066] When ultrasonic waves are incident from probe A, and received by probe B, the following relationship exists:

[0067]

[0068] When ultrasonic waves are incident from probe B, the following relationship holds when ultrasonic waves are received by probe A:

[0069]

[0070] Subtracting the above two equations, we get:

[0071]

[0072] It can be seen that the expression of flow velocity v no longer contains the ultrasonic wave velocity c.

[0073] The algorithm formula in the G step is:

[0074]

[0075] Where ΔQj is the flow rate at any time, V a is the average flow velocity at any time.

[0076] See also Figures 1 to 5In order to achieve long-term outdoor real-time detection, the present invention avoids the influence of water temperature on the detection progress and reduces the influence of major factors such as mechanical and time delays on the flow velocity measurement. The present invention adopts a multi-distance layered anti-interference open channel flow measurement device, and scientifically and cleverly builds an ultrasonic cross-sectional flow velocity measurement model and a flow measurement noise reduction model, and inserts an intelligent algorithm for flow velocity-area water measurement, and avoids the influence of water temperature on the detection progress through the sound velocity elimination algorithm. The specific method steps and principles are as follows:

[0077] The present invention has a plurality of strip-shaped notches 3 formed in the longitudinal direction on the water flow side wall of open channel agricultural irrigation facilities such as canals and troughs, wherein at least two strip-shaped notches 3 spaced at a certain interval are formed on the canal side wall 1 on one side. The same set of open channel flow measurement devices is generally provided with no less than three strip-shaped notches 3, and the strip-shaped notches 3 are used to install the embedded mounting seat 4, and the strip-shaped notches 3 can be embedded during construction, or can be grooved on site during installation. The embedded mounting seat 4 is fixedly provided in the strip-shaped notches 3, and the embedded mounting seat 4 can be made of a whole stainless steel or aluminum alloy component, which is effectively connected and fixed to the surface of water conservancy facilities such as canals, and the connection part has a smooth transition, and can be guaranteed to be stable under the action of water flow.

[0078] The embedded mounting seat 4 can adopt a variety of structural forms, preferably a structure with an arc-shaped plug-in groove, specifically including a bottom plate surface 5, an outer arc-shaped surface 6 and an arc-shaped plug-in groove 7. The bottom plate surface 5, the outer arc-shaped surface 6 and the arc-shaped plug-in groove 7 are fixed as a whole and can be processed by casting or welding. The cross-sectional outer contour of the embedded mounting seat 4 is the same as the cross-sectional outer contour of the strip-shaped notch 3. The bottom plate surface 5 is located on the inner side of the strip-shaped notch 3, and the two sides of the bottom plate surface 5 are symmetrically fixed with the outer arc-shaped surfaces 6, and the arc-shaped plug-in groove 7 is provided between the two outer arc-shaped surfaces 6. The connection part between the two outer arc-shaped surfaces 6 and the bottom plate surface 5 is smoothly connected with the side wall 1 of the water channel.

[0079] Flow measuring units are installed in the arc-shaped plug-in grooves 7. For example, the same open channel flow measuring device is provided with three flow measuring units, and the three are respectively recorded as flow measuring units: No. 1 flow measuring unit 8, No. 2 flow measuring unit 9, and No. 3 flow measuring unit 10. To this end, two strip-shaped slots 3 are provided at a certain interval on the inner wall of one side of the canal side wall 1, wherein the No. 1 flow measuring unit 8 is installed in one of the strip-shaped slots 3, and the No. 2 flow measuring unit 9 is installed in the other strip-shaped slot 3. A strip-shaped slot 3 is provided on the inner wall of the other side of the canal side wall 1, and the No. 3 flow measuring unit 10 is installed in the strip-shaped slot 3. The No. 3 flow measuring unit 10 is provided corresponding to the No. 1 flow measuring unit 8 and the No. 2 flow measuring unit 9, respectively.

[0080] The arc-shaped plug-in slot 7 has strip-shaped notches distributed along the length direction, that is, the side of the arc-shaped plug-in slot 7 close to the ditch water body is set as an open surface, and the arc-shaped sensor housing 11 is installed in the arc-shaped plug-in slot 7, which has good stability after being fixed. The arc radius of the arc-shaped plug-in slot 7 is the same as the outer arc radius of the arc-shaped sensor housing 11. After the arc-shaped sensor housing 11 is installed in the arc-shaped plug-in slot 7, it can be rotated at a certain angle to adjust the direction of the sensor.

[0081] The arc sensor housing 11 is a long strip-shaped cavity structure with one end open. The interior of the arc sensor housing 11 is set as a sensor installation cavity 12 for installing the sensor. The outer wall of the arc sensor housing 11 is provided with a plurality of sensor detection holes 14 corresponding to the open surface of the arc plug-in slot 7. The inner wall of the arc sensor housing 11 is provided with a plurality of sensor clamping and fixing grooves 15. A flow measuring sensor 16 is fixed on the sensor clamping and fixing grooves 15. The flow measuring sensor 16 adopts an ultrasonic transducer, a radar flow measuring sensor or other sensors. The detection end of the flow measuring sensor 16 is located in the sensor detection hole 14. At the same time, the sensor installation cavity 11 is effectively sealed. The bottom end of the arc sensor housing 11 is closed or sealed by the end seal 13. The upper end of the arc sensor housing 11 is also sealed by the end seal 13, which ensures good waterproof performance, and the anti-interference and anti-aging performance are also improved.

[0082] In addition, in order to facilitate the fixation of the arc sensor housing and adjust a certain angle as needed, the present invention adopts a structure of a toothed disk and a toothed ring. An adjustable toothed disk 17 is fixedly provided at the upper end of the arc sensor housing 11, and a fixed ring 18 with a toothed ring is fixedly provided at the upper end of the arc-shaped plug-in groove 7. The toothed ring on the fixed ring 18 cooperates with the tooth structure on the adjustable toothed disk 17. After the arc sensor housing 11 and the adjustable toothed disk 17 are rotated at a certain angle, they can be fixed by clamping the adjustable toothed disk 17 and the fixed ring 18, which is convenient for adjustment as needed.

[0083] The method of the present invention is described in detail below in conjunction with specific embodiments:

[0084] Taking the use of three flow measuring units as an example, first connect more than three flow measuring units, check the waterproof sealing, and establish electrical connections between the flow measuring units and the controllers on the bank of the canal. Then, plug the flow measuring units into the embedded mounting seat one by one, adjust the angle of the flow measuring unit according to the detection requirements of the flow measuring sensor, and meet the requirements of two-to-two shooting in multiple flow measuring units. Then, the distance parameter L of the equipment is measured by the flow measuring unit in the air without flowing water between the flow measuring units on both sides. Then, the attitude difference of the measuring point is obtained through the attitude sensor integrated in the flow measuring unit, and the specific 3D coordinate position of the detection signal or detection wave transceiver for different depths in each flow measuring sensor is solved through 3D attitude analysis, and the precise distance between the flow measuring sensors at each measuring point in the flow measuring unit is further obtained. Due to the large difference in flow velocity between the layers of the open channel, the flow velocity Vi of each water layer is obtained by layered measurement, i∈M, and the water layers are numbered from top to bottom.

[0085] In order to eliminate the influence of ultrasonic wave velocity c on the measurement result of the measured fluid velocity v, the present invention uses a sound velocity elimination algorithm to weaken the influence of the sound velocity in the measurement, avoid the serious influence of the sound velocity in the presence of sediment, and effectively prevent the measurement error from being too large. The sound velocity elimination algorithm is as follows:

[0086] When ultrasonic waves are incident from probe A, and received by probe B, the following relationship exists:

[0087]

[0088] When ultrasonic waves are incident from probe B, the following relationship holds when ultrasonic waves are received by probe A:

[0089]

[0090] Subtracting the above two equations, we get:

[0091]

[0092] It can be seen that the expression of flow velocity v no longer contains the ultrasonic wave velocity c, thus avoiding the interference of the ultrasonic wave velocity c on the measurement result when it changes due to the influence of temperature, greatly improving the accuracy of the relevant ultrasonic measurement data and ensuring the measurement accuracy.

[0093] In addition, the formula for calculating the speed of sound can be expressed by the sound pressure, that is, the sound pressure (p) 2 = sound intensity (I) × medium density (ρ) × sound speed (C). The unit of sound intensity is W / m 2 , density unit is kg / m 3 , the speed of sound is m / s;

[0094] Adaptive filtering sound velocity elimination algorithm is used: the filter parameters are automatically adjusted according to the statistical characteristics of the input signal. In flow measurement, the adaptive filtering algorithm can be used to filter out noise signals or interfering frequency components caused by changes in sound velocity, thereby improving the accuracy of flow signals.

[0095] Take the first layer of rectangular pipe in the measurement section as an example. In a group of ultrasonic transducers, the first ultrasonic transducer emits a sound wave which is reflected by the reflection plane to the second ultrasonic transducer. The transmission time t of the sound wave along the airflow direction is collected. ab ; The second ultrasonic transducer emits a sound wave which is reflected by the reflection plane to the first ultrasonic transducer, and collects the transmission time t of the sound wave against the airflow direction; then the relationship between the propagation time and the flow velocity v is listed, and the sound velocity c is eliminated after the combination, and the formula for the flow velocity v is as follows:

[0096]

[0097] Where l is the distance from the ultrasonic transducer to the reflection point, and α is the angle between the ultrasonic propagation direction and the horizontal direction; finally, according to the above method, the flow velocities Vi of multiple fluids in the multi-layer rectangular pipe are measured, and the mathematical function relationship is combined to obtain the estimated value of the average flow velocity of the pipe multiplied by the flow channel cross-sectional area A of the measuring section to obtain the final flow rate Q, and the formula is: Where k is less than or equal to the number of layers of rectangular tubes.

[0098] Finally, the area of ​​the water layer Si = f(L, K, P) is calculated by the spacing K of the flow measuring sensors on the split measuring device and the attitude quaternion data P (w, x, y, z) of the transceiver equipment. The relatively accurate cumulative flow rate can be calculated based on the sampling interval ΔT and the total metering time T.

[0099] The average flow velocity at any time is:

[0100]

[0101] The average flow rate at any time is: ΔQ j =V aj ΔT;

[0102] Since the total number of samples is:

[0103]

[0104] So the total flow is:

[0105]

[0106] Considering the large integral error caused by rectangular integration, the formula can be corrected as follows:

[0107]

[0108] The present invention builds an ultrasonic cross-sectional flow velocity measurement model and a flow measurement noise reduction model, and incorporates an intelligent algorithm for flow velocity-area water measurement, thereby maximizing the flow velocity detection accuracy, reducing the impact of major factors such as mechanical and time delays on flow velocity measurement, and significantly improving measurement accuracy.

[0109] The above content is a further detailed description of the present invention in combination with specific implementation methods. It cannot be considered that the specific implementation of the present invention is limited to these descriptions. For ordinary technicians in the technical field to which the present invention belongs, simple modifications and substitutions made without departing from the concept of the present invention should be deemed to belong to the scope of protection of the present invention.

Claims

1. A multi-distance layered anti-interference open channel flow measurement device, comprising a channel side wall (1) and a channel bottom (2), characterized in that: The inner wall surfaces of the two opposite sides of the water channel side wall (1) are respectively provided with a plurality of strip-shaped slots (3) along the longitudinal direction, wherein the water channel side wall (1) located on one side is provided with at least two strip-shaped slots (3) spaced at a certain interval, and embedded mounting seats (4) are respectively fixedly arranged in the strip-shaped slots (3), and the side of the arc-shaped plug-in groove (7) close to the water body of the ditch is arranged as an open surface, and flow measuring units are respectively installed in the arc-shaped plug-in groove (7), and a plurality of flow measuring sensors (16) are installed in the flow measuring units at intervals along different water levels.

2. A multi-distance layered anti-interference open channel flow measurement device according to claim 1, characterized in that: Two strip-shaped slots (3) are provided on the inner wall of one side of the water channel side wall (1) at a certain interval, a first flow measuring unit (8) is installed in one of the strip-shaped slots (3), and a second flow measuring unit (9) is installed in the other strip-shaped slot (3); a strip-shaped slot (3) is provided on the inner wall of the other side of the water channel side wall (1), and a third flow measuring unit (10) is installed in the strip-shaped slot (3), and the third flow measuring unit (10) is respectively arranged corresponding to the first flow measuring unit (8) and the second flow measuring unit (9).

3. The multi-distance layered anti-interference open channel flow measurement device according to claim 1, characterized in that: The embedded mounting seat (4) comprises a bottom plate surface (5), an outer arcuate surface (6) and an arcuate plug-in groove (7); the bottom plate surface (5) is located on the inner side of the strip-shaped notch (3); the outer arcuate surfaces (6) are symmetrically fixedly arranged on both sides of the bottom plate surface (5); and the arcuate plug-in groove (7) is arranged between the two outer arcuate surfaces (6).

4. The multi-distance layered anti-interference open channel flow measurement device according to claim 1, characterized in that: The flow measuring unit comprises a curved surface sensor housing (11), a sensor mounting cavity (12), an end seal (13) and a plurality of flow measuring sensors (16); the curved surface sensor housing (11) is a long strip-shaped cavity structure with one end open; the interior of the curved surface sensor housing (11) is provided with a sensor mounting cavity (12); and the open end of the curved surface sensor housing (8) is sealed by the end seal (13).

5. A system for monitoring the compaction and settlement of deep water sediments according to claim 4, characterized in that: The outer wall of the arc surface sensor housing (11) is provided with a plurality of sensor detection holes (14) corresponding to the open surface of the arc-shaped plug-in slot (7), a flow measuring sensor (16) is installed in the sensor installation cavity (12), and the detection end of the flow measuring sensor (16) is located in the sensor detection hole (14).

6. A system for monitoring the compaction and settlement of deep water sediments according to claim 4, characterized in that: A sensor clamping and fixing groove (15) corresponding to the sensor detection hole (14) is provided on the inner wall of the sensor installation cavity (12), and a flow measuring sensor (16) is fixed on the sensor clamping and fixing groove (15).

7. A system for monitoring the compaction and settlement of deep water sediments according to claim 1 or 7, characterized in that: The flow measuring sensor (16) is an ultrasonic transducer or a radar flow measuring sensor.

8. A flow measurement method using a multi-distance layered anti-interference open channel flow measurement device, comprising the following steps: A. First, connect three or more flow measuring units, check the waterproof sealing, and establish electrical connections between the flow measuring units and the controllers on the bank of the canal; B. Then, the flow measuring units are inserted and installed in the pre-buried mounting bases one by one, and the angles of the flow measuring units are adjusted according to the detection requirements of the flow measuring sensors to meet the requirements of the two-to-two cross-reflection of multiple flow measuring units; C. Then, the distance parameter L of the device is measured by the flow measuring unit in the air without flowing water between the flow measuring units on both sides; D. The attitude sensor integrated in the flow measurement unit is used to obtain the attitude difference of the measuring point, and the specific 3D coordinate position of the detection signal or detection wave transceiver of each flow measurement sensor for different depths is solved through 3D attitude analysis, and the precise distance between the flow measurement sensors at each measuring point in the flow measurement unit is further obtained; E. Since the flow velocity of each layer in the open channel is quite different, the flow velocity of each water layer Vi is obtained by layered measurement, i∈M, and the water layers are numbered from top to bottom; F. Then, the sound velocity elimination algorithm is used to weaken the influence of the sound velocity in the measurement, so as to avoid the serious influence of the sound velocity in the presence of sediment, which will cause excessive measurement errors. G. Finally, the area of ​​the water layer Si = f (L, K, P) is calculated through the spacing K of the flow measuring sensors on the split measuring device and the attitude quaternion data P (w, x, y, z) of the transceiver equipment. The relatively accurate cumulative flow rate can be calculated based on the sampling interval ΔT and the total metering time T.

9. A flow measurement method using a multi-distance layered anti-interference open channel flow measurement device according to claim 8, characterized in that: The specific algorithm for eliminating the sound speed term in step F is as follows: When ultrasonic waves are incident from probe A, and received by probe B, the following relationship exists: When ultrasonic waves are incident from probe B, the following relationship holds when ultrasonic waves are received by probe A: Subtracting the above two equations, we get: It can be seen that the expression of flow velocity v no longer contains the ultrasonic wave velocity c.

10. A flow measurement method using a multi-distance layered anti-interference open channel flow measurement device according to claim 8, characterized in that: The algorithm formula in the G step is: Where ΔQj is the flow rate at any time, V a is the average flow velocity at any time.

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