Flow velocity measuring device and method

Abstract

The invention provides a flow velocity measuring device and method.The flow velocity measuring device comprises a suspension assembly and an angle measuring assembly, the suspension assembly comprises a suspension frame and an angle scale, the suspension frame is installed on the ground, the angle scale is connected with the suspension frame, the suspension assembly comprises a suspension knob, a plumb bob body and a suspension body, the suspension knob is rotatably connected with the suspension frame, and the plumb bob body is connected with the suspension knob. The plumb bob body and the suspension body are both connected with the suspension knob, the plumb bob body is located above the fluid and coincides with a zero graduation line on the angle scale, the suspension body is arranged in the fluid, and an angle formed by a connecting line between the suspension body and the suspension knob and a connecting line between the plumb bob body and the suspension knob is a measurement deflection angle. Measuring the deflection angle and determining the fluid flow velocity according to the flow velocity comparison table. The flow velocity measuring device has the advantages of being easy and convenient to operate and high in measuring precision.

Description

Technical Field

[0001] The present invention relates to the technical field of water conservancy monitoring, and specifically, to a flow velocity measuring device and method. Background Art

[0002] In many fields such as water conservancy, environmental monitoring, and mines, accurately measuring the water flow velocity is crucial. Flow velocity data is of key significance for aspects such as water conservancy project planning, water resource management, environmental assessment, and fluid control in industrial production processes.

[0003] In related technologies, flow velocity measurement technologies mainly use electromagnetic and ultrasonic flow meters. Since such flow meters need to be continuously powered to work properly, power supply becomes a huge challenge when conducting long-term measurements and monitoring in the wild. Whether using battery power supply or laying cables for power supply, it means a high cost investment. Batteries need to be frequently replaced, which not only increases the labor cost but also may lead to data loss due to battery power depletion; while laying cables faces the problems of long-distance wiring and high infrastructure construction costs.

[0004] Secondly, these flow meters that rely on electronic components have poor environmental adaptability. Electronic components have relatively strict requirements for the working environment. In a humid environment, electronic components are easily damaged by moisture, affecting the measurement accuracy and the service life of the instrument. In waters with a high sediment content, the corrosive effect of sediment will accelerate the aging and damage of electronic components, resulting in frequent instrument failures, increasing the maintenance cost and downtime. Summary of the Invention

[0005] The present invention aims to solve at least one of the technical problems in the related technologies to some extent.

[0006] For this purpose, an embodiment of the present invention provides a flow velocity measuring device and method, and the flow velocity measuring device has the advantages of simple and convenient operation and high measurement accuracy.

[0007] The flow velocity measuring device according to an embodiment of the present invention includes:

[0008] A suspension assembly, the suspension assembly includes a suspension bracket and an angle disk, the suspension bracket is installed on the ground, and the angle disk is connected to the suspension bracket;

[0009] Angle measuring component. The suspension component includes a suspension knob, a plumb body, and a suspended body. The suspension button is rotatably connected to the suspension bracket. The plumb body and the suspended body are both connected to the suspension knob. The plumb body is located above the fluid and coincides with the zero scale line on the angle scale. The suspended body is placed in the fluid. The angle formed between the line connecting the suspended body and the suspension knob and the line connecting the plumb body and the suspension knob is the measured deflection angle, and the fluid flow rate is determined according to the flow rate comparison table based on the measured deflection angle.

[0010] The overall device of the flow rate measuring device in the embodiments of the present invention adopts a pure mechanical structure and does not rely on electronic components and external power supply. When measuring and monitoring in the wild for a long time, there is no need to consider the problem of continuous power supply, avoiding the high cost of frequent battery replacement or cable laying, and reducing the input of manpower and material resources. In addition, in areas with complex terrain or inconvenient transportation in the wild, the staff can easily transport it to the measurement site and quickly complete the installation, greatly improving the work efficiency.

[0011] In some embodiments, the angle measuring component further includes a suspension line. The suspension knob is connected to the plumb body through the suspension line, and the suspension knob is connected to the suspended body through the suspension line.

[0012] In some embodiments, the wire diameter of the suspension line is less than or equal to 0.2 mm.

[0013] In some embodiments, in the plane of the horizontal plane, the cross-sectional contour of the suspended body is streamlined.

[0014] In some embodiments, the density of the suspended body is greater than the density of the fluid.

[0015] The flow rate measuring method in the embodiments of the present invention. The flow rate measuring method is completed according to the flow rate measuring device in any one of the above embodiments, and is characterized by including the following steps:

[0016] Suspend the plumb body and the suspended body on the suspension knob on the suspension bracket;

[0017] Suspend the plumb body in the air and make the suspension line between the plumb body and the suspension knob coincide with the zero scale line on the angle scale, and immerse the suspended body into the fluid;

[0018] After the suspended body is stable, record the measured deflection angle α between the line connecting the suspended body and the suspension knob and the line connecting the plumb body and the suspension knob;

[0019] Determine the flow rate corresponding to the measured deflection angle on the flow rate comparison table according to the measured deflection angle α.

[0020] In some embodiments, for the flow velocity V in the flow velocity comparison table, the flow velocity calculation formula is used: where ρ1 is the density of the suspended body, ρ0 is the density of the fluid, V obj is the volume of the suspended body, g is the acceleration due to gravity, C d is the empirical drag coefficient, and A is the flow-facing area.

[0021] In some embodiments, the flow velocity calculation formula further includes a correction coefficient K, that is, the corrected flow velocity calculation formula: The range of the correction coefficient is: 0.85 ≤ K ≤ 1.25.

[0022] In some embodiments, the value of the correction coefficient K is obtained by comparing the measured result of the flowmeter with the calculation result of the flow velocity calculation formula.

[0023] In some embodiments, the following steps are further included: changing the depth and position of the suspended body in the measurement section, performing multiple measurements, and obtaining the average cross-sectional flow velocity. Description of the Drawings

[0024] Figure 1 is a schematic diagram of the use of the flow velocity measurement device according to an embodiment of the present invention.

[0025] Reference Signs:

[0026] 100, water surface,

[0027] 1, suspension assembly, 11, suspension bracket, 12, angle dial,

[0028] 2, angle measurement assembly, 21, suspension knob, 22, plumb body, 23, suspended body, 24, suspension wire,

[0029] 3, flow velocity comparison table. Detailed Embodiments

[0030] The embodiments of the present invention will be described in detail below. The examples of the embodiments are listed in the drawings. The embodiments described below with reference to the drawings are exemplary and are intended to explain the present invention and should not be construed as limiting the present invention.

[0031] As Figure 1 shown, the flow velocity measurement device according to an embodiment of the present invention includes: a suspension assembly 1 and an angle measurement assembly 2.

[0032] The suspension assembly 1 includes a suspension bracket 11 and an angle dial 12. The suspension bracket 11 is installed on the ground, and the angle dial 12 is connected to the suspension bracket 11. The suspension assembly 1 includes a suspension knob 21, a plumb body 22, and a suspension body 23. The suspension button is rotatably connected to the suspension bracket 11. Both the plumb body 22 and the suspension body 23 are connected to the suspension knob 21. The plumb body 22 is located above the fluid and coincides with the zero scale line on the angle dial 12. The suspension body 23 is placed in the fluid. The angle formed by the connection line between the suspension body 23 and the suspension knob 21 and the connection line between the plumb body 22 and the suspension knob 21 is the measured deflection angle. The fluid flow rate is determined according to the flow rate comparison table 3 based on the measured deflection angle.

[0033] Specifically, as Figure 1 shown, the suspension bracket 11 can be fixed to the ground by plugging, screws, anchor bolts, etc., so as to play a role in supporting the overall device and providing an installation basis for other components. The angle dial 12 is installed on the suspension bracket 11 through bolts, etc., and it is necessary to ensure that the zero scale line of the angle dial 12 is parallel to the vertical direction to facilitate subsequent reading of angle data. Among them, the angle dial 12 can adopt a measuring element with an angle measuring function such as a protractor or a slope gauge.

[0034] Taking the water body (i.e., fresh water) in an open channel as an example, as Figure 1 shown, the water flow direction is from left to right. The suspension knob 21 is rotatably connected to the suspension bracket 11 (for example, the suspension knob 21 is connected to the suspension bracket 11 through components such as bearings). Both the plumb body 22 and the suspension body 23 can be connected to the suspension knob 21 through a wire rope, etc. The plumb body 22 is located above the water surface 100. When in use, when there is no water flow acting, both the plumb body 22 and the suspension body 23 are vertically downward, indicating the zero scale of the angle dial 12. When there is water flow, the suspension body 23 is placed in the fluid. The water flow generates a resistance on the suspension body 23, causing the suspension body 23 to deflect. Since the suspension body 23 is connected to the suspension knob 21, the deflection of the suspension body 23 will drive the suspension knob 21 to rotate, and then an included angle is formed between the connection line between the suspension body 23 and the suspension knob 21 and the connection line between the plumb body 22 and the suspension knob 21, that is, the measured deflection angle. Thus, the corresponding flow rate can be determined from the flow rate comparison table 3 according to the measured deflection angle. It should be clear that when the suspension body 23 drives the suspension knob 21 to rotate under the action of the fluid, the plumb body 22 does not rotate with the rotation of the suspension knob 21 to reduce the error of the measured deflection angle.

[0035] It should be noted that when the flow rate measuring device of the embodiment of the present invention is in use, the suspension body 23 is immersed in the fluid. According to the Newton resistance balance principle, the resultant force of the water flow drag force, gravity, and buoyancy on the suspension body 23 in the fluid reaches equilibrium. Thus, the measured deflection angle measured by the flow rate measuring device of the embodiment of the present invention can correspond to the fluid flow rate.

[0036] That is, according to the flow velocity calculation formula and by measuring the deflection angle, the flow velocity corresponding to each deflection angle can be calculated in advance, thereby forming the flow velocity comparison table 3, so as to use the flow velocity measuring device of the embodiment of the present invention to perform multi-point measurements on different flow segments of the same fluid subsequently. Where ρ1 is the density of the suspension body 23, ρ0 is the density of the fluid, V obj is the volume of the suspension body 23, g is the acceleration due to gravity, C d is the empirical drag coefficient, and A is the flow-facing area.

[0037] In other words, the flow velocity measuring device of the embodiment of the present invention can determine the flow velocity of the fluid according to the flow velocity comparison table 3 through the measurement deflection angle generated by the suspension body 23 under the action of the water flow resistance. This measurement method is intuitive and easy to understand, does not require complex electronic signal processing and data analysis. The operator only needs to read the angle value on the angle scale 12 and then refer to the flow velocity comparison table 3 to obtain the flow velocity data, which reduces the requirements for the professional skills of the operator and is convenient for wide application.

[0038] Therefore, the overall device of the flow velocity measuring device of the embodiment of the present invention adopts a pure mechanical structure and does not rely on electronic components and external power supply. When performing long-term measurement and monitoring in the wild, there is no need to consider the problem of continuous power supply, avoiding the high cost of frequent battery replacement or cable laying, and reducing the input of manpower and material resources. In addition, in areas with complex terrain or inconvenient transportation in the wild, the staff can easily transport it to the measurement site and quickly complete the installation, greatly improving the work efficiency.

[0039] In addition, the flow velocity measuring device of the embodiment of the present invention does not use electronic components, and the device is not affected by humid environments and sediment corrosion. In humid wild environments or waters with high sediment content, there will be no problems of electronic components being damaged by moisture or corroded by sediment, ensuring the measurement accuracy and the service life of the instrument, reducing the maintenance cost and downtime, and improving the reliability and stability of the device.

[0040] In some embodiments, the angle measurement assembly 2 further includes a suspension line 24. The suspension knob 21 is connected to the plumb body 22 through the suspension line 24, and the suspension knob 21 is connected to the suspension body 23 through the suspension line 24.

[0041] Specifically, as Figure 1As shown, one end of the suspension line 24 is fixed to the suspension knob 21, and the other end is fixed to the plumb body 22, so that the plumb body 22 can be vertically downward under the action of gravity and is in a relatively flexible state in the overall structure of the device. When the device is installed, the plumb body 22 naturally hangs down under gravity, and its position corresponds to the zero scale line on the angle scale 12, providing a reference for subsequent measurements. Similarly, one end of the suspension line 24 is connected to the suspension knob 21, and the other end is connected to the suspension body 23, and the suspension body 23 is placed in the fluid. When the water flows, the water flow generates a resistance on the suspension body 23. Due to the connection of the suspension line 24, the offset of the suspension body 23 will be transmitted to the suspension knob 21 through the suspension line 24, causing the suspension knob 21 to rotate to form a measured deflection angle.

[0042] It can be understood that the use of the suspension line enables the plumb body 22 and the suspension body 23 to have better flexibility when connected to the suspension knob 21. Compared with a rigid connection, the suspension line 24 allows the plumb body 22 and the suspension body 23 to swing and rotate freely within a certain range. This is very important for accurately capturing the force exerted by the water flow on the suspension body 23 and reflecting the angular changes caused by this force. For example, in the case where the water flow direction is unstable or there are small fluctuations, the suspension line 24 can enable the suspension body 23 to more sensitively follow the changes in the water flow and adjust its position, thereby more accurately measuring the flow rate.

[0043] In addition, due to the certain flexibility of the suspension line 24, when installing the device, it is more convenient to connect the plumb body 22 and the suspension body 23 to the suspension knob 21. Moreover, if the position of the device needs to be adjusted or components need to be replaced, simply adjusting the length of the suspension line 24 or re-fixing the connection point of the suspension line 24 is relatively simple, saving the time and effort for installation and maintenance.

[0044] Preferably, the wire diameter of the suspension line 24 is less than or equal to 0.2 mm. It can be understood that the suspension line 24 can reduce the interference of the device's own structure on the measurement results. Since the suspension line 24 itself has a relatively light mass, under the action of the water flow, its influence on the suspension body 23 and the plumb body 22 is small, and it can more truly reflect the resistance of the water flow on the suspension body 23.

[0045] That is to say, the extremely thin suspension line 24 has an extremely small self-mass. Under the action of the water flow, the resistance and inertia it generates can be almost ignored. That is, the suspension line 24 will not cause obvious interference to the movement of the suspension body 23, enabling the suspension body 23 to more purely feel the force of the water flow. Thus, it can more accurately reflect the quantitative relationship between the water flow velocity and the measured deflection angle, greatly improving the accuracy of the flow rate measurement.

[0046] Optionally, the suspension line 24 can be selected from carbon lines or fishing lines, etc.

[0047] In some embodiments, within the plane of the horizontal plane, the cross-sectional contour of the suspension body 23 is streamlined. It can be understood that the outer contour of the suspension body 23 adopts a streamlined contour, making the surface of the suspension body 23 smooth to reduce the influence of turbulence. That is to say, the streamlined design conforms to the principles of fluid mechanics and can significantly reduce the form drag of the suspension body 23 in flowing water. When the water flow passes through the suspension body 23, the streamlined contour enables the water flow to smoothly bypass the suspension body 23, reducing the separation of the water flow and the generation of vortices. Thus, the water flow resistance received by the suspension body 23 is mainly related to the water flow velocity, rather than being interfered by irregular form drag.

[0048] Optionally, the shape of the suspension body 23 can be a sphere, a cylinder, or a polyhedron with a streamlined outer contour, etc. Preferably, the suspension body 23 is a stainless steel sphere.

[0049] In some embodiments, the density of the suspension body 23 is greater than the density of the fluid. It can be understood that when the density of the suspension body 23 is greater than the density of the fluid, the suspension body 23 has a tendency to sink in the fluid. This sinking tendency keeps the suspension line 24 always in a tensioned state, ensuring the stability and effectiveness of the connection between the suspension body 23 and the suspension knob 21. The suspension line 24 can accurately transmit the acting force of the water flow on the suspension body 23 to the suspension knob 21, causing the suspension knob 21 to rotate accordingly according to the water flow situation, and then forming an accurate measurement deflection angle.

[0050] The flow velocity measurement method of the embodiments of the present invention will be described below.

[0051] The flow velocity measurement method of the embodiments of the present invention, the flow rate measurement method is completed by the flow rate measurement device according to any one of the above embodiments, and is characterized in that it includes the following steps:

[0052] Suspend the plumb body 22 and the suspension body 23 on the suspension knob 21 of the suspension bracket 11. It can be understood that the plumb body 22 and the suspension body 23 are respectively connected to the suspension knob 21 on the suspension bracket 11 by the suspension line 24. Such a connection method constructs the basic structure of the entire measurement system, enabling the plumb body 22 and the suspension body 23 to generate relative motion under the action of the water flow, creating conditions for subsequent measurement of the flow velocity.

[0053] Suspend the plumb body 22 in the air and make the suspension line 24 between the plumb body 22 and the suspension knob 21 coincide with the zero scale line on the angle scale 12, and immerse the suspension body 23 into the fluid. The plumb body 22 is vertically downward under the action of gravity, and the suspension line 24 between it and the suspension knob 21 coincides with the zero scale line of the angle scale 12, providing an initial reference for subsequent measurement of the deflection angle. And immersing the suspension body 23 into the fluid makes it directly contact with the fluid to feel the acting force of the water flow.

[0054] It should be noted that, in response to different fluid densities (such as seawater), replaceable counterweights may be provided to adjust the effective density of the suspension body 23 .

[0055] After the suspension body 23 is stabilized, the measured deflection angle α between the line between the suspension body 23 and the suspension knob 21 and the line between the plumb bob 22 and the suspension knob 21 is recorded. That is to say, when the suspension body 23 is placed in the fluid, the water flow will produce resistance to it, causing it to deflect. Waiting for the suspension body 23 to stabilize is to ensure that the deflection angle measured is under the action of the stable water flow, and to avoid inaccurate measurements caused by water flow fluctuations or initial shaking of the suspension body 23. Of course, when recording the measured deflection angle α at the same measurement depth, in order to ensure the accuracy of the readings, the method of taking the average of multiple readings can be used to reduce the error.

[0056] The flow velocity corresponding to the measured deflection angle on the flow velocity comparison table 3 is determined according to the measured deflection angle α. In other words, the flow velocity comparison table 3 is a correspondence table between the measured deflection angle and the flow velocity obtained through a large number of experiments and theoretical calculations. After obtaining the measured deflection angle α, it is only necessary to find the corresponding flow velocity value in the flow velocity comparison table 3 to obtain the flow velocity of the fluid. This method is simple and intuitive, and does not require complex calculations and analysis. The accuracy of the flow velocity comparison table 3 depends on the accuracy of the previous experiments and the integrity of the data. In practical applications, it is necessary to ensure that the flow velocity comparison table 3 used matches the measuring device and the measuring environment to ensure the reliability of the measurement results.

[0057] In some embodiments, the flow rate V in the flow rate comparison table 3 is calculated using the flow rate calculation formula: Wherein, ρ1 is the density of the suspension body 23, ρ0 is the density of the fluid, V obj is the volume of the suspended body 23, g is the acceleration due to gravity, C d is the empirical resistance coefficient, and A is the headwind area (i.e. the projected area of ​​the suspension body in the plane perpendicular to the direction of the water flow).

[0058] In some embodiments, the flow rate calculation formula also includes a correction coefficient K, that is, a corrected flow rate calculation formula: The range of the correction coefficient is: 0.85≤K≤1.25.

[0059] It is understandable that, during the measurement process, the above theoretical formula is corrected due to the influence of factors such as the resistance of the suspension line 24 in the water, the change of the empirical resistance coefficient at different flow rates, the density of the water body at different temperatures in the field, and the visual error of observation. Among them, the above correction coefficient is the correction coefficient of the flow rate of the water body (i.e., fresh water) in the open channel at normal temperature and pressure. Of course, in actual applications, the correction coefficient can be compared and measured in advance.

[0060] In order to adapt to the rapid measurement of water flow velocity in various scenarios such as the field and underground mines, the above formula is improved as follows:

[0061] Selection of the suspended body: Select an austenitic stainless steel ball (type 304 stainless steel ball) with a radius r of 0.01 m and a density ρ1 of 7.93 g / cm 3 ; The suspension line is selected as a carbon line with a wire diameter less than or equal to 0.2 mm; In the field environment, the water density ρ0 is 1 g / cm 3 ; The water resistance coefficient C d needs to be determined according to the flow conditions, about 0.47 in the case of smooth sphere turbulence;

[0062] Thus, substituting the above values, we can obtain: That is to say, when using the same flow velocity measuring device to measure the flow velocity of water in a certain range, through the measured deflection angle, the corresponding water flow velocity can be quickly calculated.

[0063] In some embodiments, the value of the correction coefficient K is obtained by comparing the measured results of the flowmeter with the calculation results of the flow velocity calculation formula.

[0064] It can be understood that when drawing the flow velocity comparison table 3, the flow velocity measurement method and the flow velocity calculation formula of the embodiments of the present invention and the flowmeter can be used to measure and calculate the flow velocity at the same position respectively. According to the multiple measured results, the correction coefficient K of the flow velocity calculation formula can be obtained. Among them, the flowmeter can be an ultrasonic flowmeter or a turbine flowmeter, etc.

[0065] In some embodiments, it further includes the following steps: changing the depth and position of the suspended body 23 in the measurement section, performing multiple measurements, and obtaining the average cross-sectional flow velocity.

[0066] It can be understood that in the actual fluid environment, the flow velocities at different depths and positions often vary. For example, in a river, the flow velocities at the water surface 100 and the bottom are different, and the flow velocities near the river bank and in the center of the river are also different. By changing the depth and position of the suspended body 23 in the measurement section, the flow velocity information of different points in the measurement section can be comprehensively obtained. During specific operation, the depth of the suspended body 23 can be changed by adjusting the length of the suspension line 24, and the position of the suspended body 23 in the horizontal direction can be changed by moving the position of the suspension bracket 11 or adjusting the installation position of the suspension knob 21.

[0067] That is to say, at each selected depth and position, following the previous measurement steps, the plumb body 22 is suspended in the air and aligned with the zero scale line. The suspension body 23 is immersed in the fluid. After stabilization, the measured deflection angle is recorded, and then the flow velocity is determined according to the flow velocity comparison table 3. Multiple measurements are carried out to improve the accuracy and reliability of the measurement. Since there may be certain errors in each measurement, these errors can be reduced by multiple measurements. For example, it may be interfered by factors such as instantaneous fluctuations of the water flow and measurement reading errors. Taking the average value of multiple measurements can effectively reduce these random errors.

[0068] Thus, the flow velocity data measured at different depths and positions are summarized, and then their average value is calculated. This average value is the average cross-sectional flow velocity of the measurement profile. The average cross-sectional flow velocity can more accurately reflect the average flow condition of the fluid within the entire measurement profile, and is of great significance for fields such as water conservancy project planning and water resource management. For example, when calculating the flow rate of a river, the average cross-sectional flow velocity is a key parameter, and it can be combined with the cross-sectional area of the measurement profile to calculate the flow rate of the river.

[0069] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present invention.

[0070] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one of such features. In the description of the present invention, the meaning of "a plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0071] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed", etc. should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or integrated; it can be a mechanical connection, an electrical connection, or communicable with each other; it can be directly connected, or indirectly connected through an intermediate medium, and can be the communication inside two elements or the interaction relationship between two elements, unless otherwise clearly limited. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0072] In the present invention, unless otherwise clearly defined or limited, the first feature being "on" or "under" the second feature may mean that the first and second features are in direct contact, or the first and second features are indirectly in contact through an intermediate medium. Further, the first feature being "above", "over" and "on top of" the second feature may mean that the first feature is directly above or obliquely above the second feature, or merely indicates that the horizontal height of the first feature is higher than that of the second feature. The first feature being "under", "below" and "beneath" the second feature may mean that the first feature is directly below or obliquely below the second feature, or merely indicates that the horizontal height of the first feature is lower than that of the second feature.

[0073] In the present invention, the terms "one embodiment", "some embodiments", "example", "specific example", "some examples", etc. mean that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic descriptions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, without contradiction, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0074] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those of ordinary skill in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A flow velocity measuring device, characterized in that, Comprising: A suspension assembly, the suspension assembly includes a suspension bracket and an angle disc, the suspension bracket is installed on the ground, and the angle disc is connected to the suspension bracket; An angle measurement assembly, the suspension assembly includes a suspension knob, a plumb bob and a suspension body, the suspension button is rotatably connected to the suspension bracket, both the plumb bob and the suspension body are connected to the suspension knob, the plumb bob is located above the fluid and coincides with the zero scale line on the angle disc, the suspension body is placed in the fluid, and the angle formed by the connection line between the suspension body and the suspension knob and the connection line between the plumb bob and the suspension knob is the measured deflection angle, and the fluid flow rate is determined according to the flow rate comparison table based on the measured deflection angle.

2. The flow rate measuring device according to claim 1, wherein The angle measurement assembly further includes a suspension line, the suspension knob and the plumb bob are connected by the suspension line, and the suspension knob and the suspension body are connected by the suspension line.

3. The flow rate measuring device according to claim 2, characterized in that, The wire diameter of the suspension line is less than or equal to 0.2 mm.

4. The flow rate measuring device according to claim 1, characterized in that, In the plane of the horizontal plane, the cross-sectional contour of the suspension body is streamlined.

5. The flow velocity measuring device according to claim 4, characterized in that, The density of the suspension body is greater than the density of the fluid.

6. A flow velocity measurement method, which is completed by the flow velocity measurement device according to any one of claims 1-5, characterized in that Including the following steps: Suspend the plumb bob and the suspension body on the suspension knob on the suspension bracket; Suspend the plumb bob in the air and make the suspension line between the plumb bob and the suspension knob coincide with the zero scale line on the angle disc, and immerse the suspension body into the fluid; After the suspension body is stable, record the measured deflection angle α between the connection line between the suspension body and the suspension knob and the connection line between the plumb bob and the suspension knob; Determine the flow rate corresponding to the measured deflection angle on the flow rate comparison table according to the measured deflection angle α.

7. The flow rate measurement method according to claim 6, characterized in that, The flow velocity V in the flow velocity comparison table is calculated using the flow velocity calculation formula: where ρ1 is the density of the suspended body, ρ0 is the density of the fluid, V obj is the volume of the suspended body, g is the acceleration due to gravity, C d is the empirical drag coefficient, and A is the flow-facing area.

8. The flow rate measurement method according to claim 7, characterized in that The flow rate calculation formula further includes a correction coefficient K, that is, the corrected flow rate calculation formula: The range of the correction coefficient is: 0.85 ≤ K ≤ 1.

25.

9. The flow velocity measurement method according to claim 8, characterized in that, The value of the correction coefficient K is obtained by comparing the measured result of the flow meter with the calculation result of the flow rate calculation formula.

10. The flow rate measurement method according to claim 6, characterized in that, Further including the following steps: Change the depth and position of the suspension body in the measurement section, conduct multiple measurements, and obtain the average cross-sectional flow rate.

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