A measuring device, system and measuring method for a wind field

Abstract

The present invention discloses a wind field measurement device, system and measurement method. The measurement device includes a traction module and a measurement module. The traction module includes a drone and a support rod. When the target measurement point belongs to a low wind speed area, Scheme A is adopted; when it belongs to a high wind speed area, Scheme B is adopted. In Scheme A, the measurement module is an anemometer. The support rod is placed horizontally and inserted under the fuselage of the drone. The support rod is provided with an anemometer and a counterweight. The anemometer is located on the oncoming flow side, and the counterweight is located on the symmetric side of the anemometer. The measured wind speed of the anemometer is the actual wind speed of the target measurement point. In Scheme B, the measurement module includes an anemometer and an acceleration sensor. The support rod is placed vertically. One end of the support rod fixes the drone, and the other end fixes the anemometer and the acceleration sensor. The measurement device is used to collect data so as to calculate the actual wind speed of the target measurement point. The above-mentioned measurement device can quickly switch the measurement position by using the drone, and respectively adopts a horizontal and a vertical support rod for low and high wind speed modes, reducing the measurement error.

Description

Technical Field

[0001] The present invention belongs to the technical field of wind field measurement, and particularly relates to a wind field measurement device, system and measurement method, and can be used to measure the wind field of the urban canopy in particular. Background Art

[0002] In recent years, with the rapid development of the national economy, all kinds of high-rise buildings and new districts have emerged as the times require. While bringing huge economic benefits to society, these newly built buildings have also greatly increased the surface roughness of the urban area, thus causing significant changes in the near-surface wind environment of the city, resulting in frequent problems such as local strong winds, haze, and pollutant accumulation in the city, seriously affecting the physical and mental health of residents. Therefore, the problems of urban wind environment and pollutant diffusion have gradually become an important contradiction in social development, and have also posed new challenges to our traditional urban planning thinking mode. How to more reasonably control the urban layout and avoid the problems of wind environment and pollutant diffusion caused by disorderly urban expansion has gradually become a hot topic of concern to scholars.

[0003] The urban wind environment generally refers to the near-surface air flow within the urban canopy. Within the urban canopy, buildings present complex landform features of "high density" and "high height". When natural wind passes through these "high" and "dense" buildings, street canyons will appear if the layout of high-rise buildings is unreasonable, and large-area air converges within the streets to form local strong winds. On the contrary, when the wind is blocked by buildings, the wind speed will decrease, causing pollutants not to diffuse, directly affecting the urban environment and the physical and mental health of residents. Therefore, it is of great importance to study the urban wind environment and pollutant diffusion. How to accurately predict the pollutant concentration in the community, evaluate the wind environment of the community, and improve the ventilation capacity and self-purification capacity of the community is the basis for solving environmental problems and an important way to achieve urban sustainable development and green community construction.

[0004] At present, the main means for measuring the urban wind field include lidar, wind measurement towers, and hot air balloons, etc. Among them, the operation cost of lidar is high and the resolution cannot meet the requirements. The wind measurement tower is fixed and cannot move and is restricted by height. Conventional low-cost balloon wind speed measurement is affected by the wind and swings greatly, and cannot stay at the measuring point in time. Therefore, there is an urgent need to provide a device for measuring the wind field, especially for measuring the wind field of the urban canopy, to solve the above-mentioned disadvantages of the existing technologies. Summary of the Invention

[0005] The purpose of the present invention is to provide a wind field measurement device, system and method, which can quickly measure the time-history wind speed at different height measuring points, and can conveniently switch the measurement position, so as to accurately and efficiently monitor the wind field at different heights in the air layer.

[0006] A measuring device for a wind field, comprising a traction module and a measurement module. The traction module includes a drone and a pole. When the wind speed at the target measurement point belongs to the low wind speed area, Scheme A is adopted; when it belongs to the high wind speed area, Scheme B is adopted.

[0007] Scheme A: The measurement module is an anemometer. The pole is placed horizontally and inserted into the lower part of the drone fuselage. The pole is provided with an anemometer and a counterweight. The anemometer is located on the oncoming flow side, and the counterweight is located on the symmetric side of the anemometer. The measured wind speed of the anemometer at the target measurement point is the actual wind speed of the target measurement point.

[0008] Scheme B: The measurement module includes an anemometer and an acceleration sensor. The pole is placed vertically. One end of the pole fixes the drone, and the other end fixes the anemometer and the acceleration sensor. The measuring device is used to collect data to calculate the actual wind speed of the target measurement point as follows:

[0009]

[0010] In the formula, is the actual wind speed of the target measurement point, is the final wind speed of the target measurement point obtained by using the anemometer, is the swaying speed of the pole end obtained by using the acceleration sensor, The horizontal wind speed dominates. is the speed generated by the rotation of the wing of the drone when hovering and pushing the air downward, is the vertical wind speed.

[0011] Further preferably, when the initial measured wind speed of the target measurement point is lower than the preset wind speed threshold, the target measurement point is in the low wind speed area; when it is higher than or equal to the preset wind speed threshold, the target measurement point is in the high wind speed area.

[0012] In the specific implementation process, the initial measured wind speed refers to the roughly measured wind speed. For example, before each measurement, the wind speed of the target measurement point or its surrounding area is preliminarily measured using components such as a rod and an anemometer, and the obtained wind speed is used as the initial measured wind speed.

[0013] Further preferably, the value range of the preset wind speed threshold is: [4, 6] m / s.

[0014] Further preferably, the final speed v1 measured by the anemometer is obtained according to the following formula:

[0015]

[0016]

[0017] In the formula, is the correction coefficient caused by the deflection angle of the anemometer, is the measured wind speed of the anemometer, θ is the angle formed by the mast and the vertical direction when the wind comes, c x is the air resistance coefficient of the anemometer, ρ is the air density at the height measured by the UAV, s Lx is the projected area of the anemometer in the horizontal direction, T is the tension generated by the mast, m is the mass of the anemometer, is the acceleration of the mast end measured by the acceleration sensor.

[0018] Among them, when θ is known, the specific value of can be obtained through wind tunnel tests to establish the mapping relationship between and and c x The air resistance coefficient of the anemometer can also be obtained through wind tunnel tests; the tension T generated by the mast is approximately equal to the weight of the anemometer, and the air density ρ at the height measured by the UAV is a constant, generally taking a value of 1.225 kg / m 3 .

[0019] Further preferably, the swaying speed at the end of the mast is calculated according to the following formula:

[0020]

[0021] In the formula, is the acceleration of the mast end measured by the acceleration sensor at the end of the mast, and t represents time.

[0022] Further preferably, the speed generated by the rotation of the wing of the UAV when hovering and pushing the air downward is calculated according to the following formula:

[0023]

[0024] In the formula, P is the output power of the UAV, M is the total mass of the UAV and the mast, and g is the acceleration due to gravity, and the direction is vertically downward.

[0025] Further preferably, the mast is a carbon fiber rod.

[0026] Further preferably, the length of the mast ranges from [80, 120] cm.

[0027] Further preferably, it further includes a collection module connected to the measurement module. The collection module is provided with a wireless transmitter and a ground receiving end, and the data collected by the measurement module is sent to the ground receiving end through the wireless transmitter.

[0028] Further preferably, the measuring device is a measuring device for the urban canopy wind field. In fact, this measuring device is applicable at near ground and a height of 200 meters.

[0029] Further preferably, the drone flies to a height of 0m - 80m for measurement.

[0030] On the other hand, the present invention provides a system of the above-mentioned measuring device, including the measuring device and a computer, the computer is connected to the measuring device, and when adopting Solution B, the computer uses the data collected by the measuring device to perform data calculation to obtain the wind speed of the target measuring point.

[0031] In addition, the present invention also provides a method for measuring a wind field, including the following steps:

[0032] First, identify whether the wind speed of the target measuring point belongs to the low wind speed area or the high wind speed area. If it belongs to the low wind speed area, adopt Solution A; if it belongs to the high wind speed area, adopt Solution B;

[0033] Then, control the drone to fly until the measuring device reaches the target measuring point, and obtain the actual wind speed of the target measuring point according to Solution A or Solution B.

[0034] For example, when implementing Solution B, first, control the drone to fly until the measuring device reaches the target measuring point, and obtain the final wind speed obtained by using the anemometer The swaying speed of the end of the boom obtained by using the acceleration sensor And the speed generated by the rotation of the wing of the drone when hovering and pushing the air downward

[0035] Then, calculate the actual wind speed at the current target measuring point by using the obtained respective speeds

[0036]

[0037] Wherein, one end of the boom is fixed to the drone, and the other end is fixed to the anemometer and the acceleration sensor.

[0038] Beneficial effects

[0039] 1. A wind field measuring device and a measuring method provided by the present invention can quickly switch the measuring position by using a drone, so as to quickly and comprehensively monitor the measuring area. In particular, the measuring device of the present invention can be applied to the wind field measurement of the urban canopy.

[0040] 2. The present invention provides low wind speed measurement and high wind speed measurement. The horizontal boom is used for low wind speed measurement. Such a setting can reduce the influence of the drone propeller on the wind field, thereby improving the low wind speed measurement accuracy. The vertical boom is used for high speed area measurement. This is considered for the safety of the drone itself. In this way, the anti-overturning ability of the drone can be improved, and the influence of the propeller on the wind field under high wind speed is small, and the accuracy requirement can be met after correction. Description of the drawings

[0041] Figure 1 This is a schematic diagram of the system for measuring the urban canopy wind field corresponding to Solution A of the embodiment of the present invention.

[0042] Figure 2 This is a schematic diagram of the system for measuring the urban canopy wind field corresponding to Solution B of the embodiment of the present invention.

[0043] Figure 3 This is a schematic diagram of the measuring device for measuring the urban canopy wind field according to the embodiment of the present invention.

[0044] Among them, the reference numerals are explained as follows:

[0045] 1 is the atmospheric boundary layer, 2 is the UAV remote controller, 3 is the UAV operator, 4 is the ground, 5 is the UAV, 6 is the carbon fiber rod, 7 is the SA210 anemometer, 8 is the acceleration sensor, 9 is the ground receiving end, 10 is the computer, and 11 is the counterweight. Detailed implementation manners

[0046] The following will further illustrate the present invention in conjunction with the embodiments. In this embodiment, the measurement of the urban canopy is taken as an example for illustration. The present invention sets Solution A and Solution B respectively for the low wind speed area and the high wind speed area to achieve wind field measurement. Among them, the low wind speed area refers to the area where the wind speed is lower than the preset wind speed threshold, and the high wind speed area refers to the area where the wind speed is higher than or equal to the preset wind speed threshold. In this embodiment, the preset wind speed threshold is set to 5 m / s. In other feasible embodiments, it can take any value within the range of 4 - 6 m / s, and the present invention does not specifically limit this. And to identify which wind speed area the target measurement point belongs to, existing technical means can be used to roughly estimate the wind speed, and then use it as the initial measured wind speed to compare with the preset wind speed threshold.

[0047] Such as Figure 1As shown, it corresponds to Solution A: A wind field measurement device provided in this embodiment includes a traction module, a measurement module, and a collection module. Among them, the traction module includes a load-carrying drone 5 and a carbon fiber rod 6 (with a certain flexibility, a length of l, and its value range is: 80 cm - 120 cm, and the diameter is about 1 cm). The measurement module is an SA210 anemometer 7. The carbon fiber rod 6 is placed horizontally and inserted into the lower part of the fuselage of the load-carrying drone 5. The SA210 anemometer 7 and a counterweight 11 are provided on the carbon fiber rod 6. The SA210 anemometer 7 is located on the oncoming flow side, and the counterweight 11 is located on the symmetric side of the SA210 anemometer 7 to achieve a balance effect. In actual application, the load-carrying drone 5 is used to bring the measurement device to the target measurement point, and then the measured wind speed collected by the SA210 anemometer 7 is the actual wind speed of the target measurement point. The collection module includes a wireless transmitter and a ground receiving end 9. The data collected by the measurement module is transmitted to the ground receiving end 9 through the wireless transmitter. Among them, the ground receiving end 9 is connected to a computer 10 through a data cable, and then the data is transmitted to the computer through the ground receiving end 9. The computer is used for functions such as storage. In other feasible embodiments, the measurement device can be equipped with a chip with data processing and storage functions. The chip can be directly connected to the measurement module to obtain the wind speed of the target measurement point. In other feasible embodiments, other models of anemometers can be selected, and the present invention does not make specific limitations on this.

[0048] As Figure 2 shown, it corresponds to Solution B: A wind field measurement device provided in this embodiment includes a traction module, a measurement module, and a collection module. Among them, the traction module includes a load-carrying drone 5 and a carbon fiber rod 6 (with a certain flexibility, a length of l, and its value range is: 80 cm - 120 cm, and the diameter is about 1 cm). The measurement module includes an SA210 anemometer 7 and an acceleration sensor 8. When the wind comes, the carbon fiber rod 6 forms an angle θ with the vertical direction. Both ends of the carbon fiber rod 6 are respectively provided with hook assemblies. The upper end is used to connect the load-carrying drone 5, and the lower end is used to fix the SA210 anemometer 7 and the acceleration sensor 8. The collection module includes a wireless transmitter and a ground receiving end 9. The data collected by the measurement module is transmitted to the ground receiving end 9 through the wireless transmitter. Among them, the ground receiving end 9 is connected to a computer 10 through a data cable, and then the data is transmitted to the computer through the ground receiving end 9. The computer is used to calculate the wind speed. In other feasible embodiments, the measurement device can be equipped with a chip with data processing functions. The chip can be directly connected to the measurement module to calculate the wind speed of the target measurement point in real time using the collected data. In other feasible embodiments, other models of anemometers can be selected, and the present invention does not make specific limitations on this. The specific calculation process is described below.

[0049] Based on the above measurement device, the wind speed measurement process is as follows:

[0050] First, identify whether the wind speed at the target measurement point belongs to the low wind speed area or the high wind speed area. If it belongs to the low wind speed area, adopt Plan A; if it belongs to the high wind speed area, adopt Plan B.

[0051] Then, control the flight of the load-carrying drone 5 until the measuring device reaches the target measurement point, and obtain the actual wind speed at the target measurement point according to Plan A or Plan B.

[0052] It should be understood that the target measurement point is determined according to the measurement requirements, and it can be a certain position or a certain height.

[0053] Regarding calculating the actual wind speed at the current target measurement point by using the obtained various speeds in Plan B Among them, the actual wind speed The calculation process is as follows:

[0054]

[0055] For the speed generated by the wing rotation of the load-carrying drone 5 when hovering at a specified position and pushing the air downward It can be calculated according to the following relationship between the output power P of the load-carrying drone 5 during flight and the speed generated by the wing rotation of the load-carrying drone 5 pushing the air downward The following relationship is as follows:

[0056]

[0057]

[0058] In the formula: p is the output power of the load-carrying drone 5, M is the total mass of the load-carrying drone 5 and the carbon fiber rod 6, and g is the acceleration due to gravity, and the direction is vertically downward.

[0059] As for the swaying speed at the end of the carbon fiber rod 6 It can be obtained according to the following calculation formula:

[0060]

[0061]

[0062] When under the action of the wind speed, the guy wire will generate a certain deflection angle, as Figure 3 shown. At this time, since the anemometer is rigidly connected to the end of the guy wire, the measuring end of the anemometer generates a θ deflection angle with the wind field. Therefore, the actually measured wind speed of the anemometer needs to be corrected.

[0063]

[0064] Among them, is the correction coefficient caused by the deflection angle of the anemometer, is the measured wind speed of the anemometer. When θ is known, the specific value of can be obtained through wind tunnel tests, and a mapping relationship between and is established.

[0065] Taking the anemometer as the research object, according to the force balance, its equation can be expressed as:

[0066]

[0067] Where: T is the tensile force generated by the carbon fiber rod 6, θ is the angle between the carbon fiber rod 6 and the vertical direction when the wind comes, c x is the air resistance coefficient of the anemometer, ρ is the air density at the measurement height of the load-carrying drone 5, s Lx is the projected area of the anemometer 7 in the horizontal direction, and m is the mass of the anemometer 7.

[0068]

[0069]

[0070] Therefore, the relationship between the acceleration at the rod end and the θ angle can be expressed as:

[0071]

[0072] Finally, can be deduced according to θ, so as to realize the correction of the measured wind speed of the anemometer and obtain

[0073] In the embodiment of the present invention, the above measurement device can measure the wind speed at each height of the urban canopy in all aspects, can efficiently and synchronously measure the wind profiles in all directions at a place, and can conveniently and quickly monitor the urban canopy.

[0074] It should be emphasized that the examples described in the present invention are illustrative rather than restrictive. Therefore, the present invention is not limited to the examples described in the specific embodiments. Any other embodiments obtained by those skilled in the art according to the technical solutions of the present invention, without departing from the purpose and scope of the present invention, whether modified or replaced, also belong to the protection scope of the present invention.​

Claims

1. A measuring device for a wind field, characterized in that: It includes a traction module and a measurement module. The traction module includes a drone and a pole. When the wind speed at the target measurement point belongs to the low wind speed area, Scheme A is adopted; when it belongs to the high wind speed area, Scheme B is adopted. Scheme A: The measurement module is an anemometer. The pole is placed horizontally and inserted into the lower part of the drone fuselage. The pole is provided with an anemometer and a counterweight. The anemometer is located on the oncoming flow side, and the counterweight is located on the symmetric side of the anemometer. The measured wind speed of the anemometer at the target measurement point is the actual wind speed of the target measurement point. Scheme B: The measurement module includes an anemometer and an acceleration sensor. The pole is placed vertically. One end of the pole is fixed to the drone, and the other end is fixed to the anemometer and the acceleration sensor. The measuring device is used to collect data for calculating the actual wind speed of the target measurement point as follows: Wherein, is the actual wind speed of the target measurement point, is the final wind speed of the target measurement point obtained by using an anemometer, is the swaying speed of the pole end obtained by using an acceleration sensor, is the speed generated by the rotation of the wing when the UAV hovers and acts on the air downward; The final velocity measured using an anemometer is obtained according to the following formula: In the formula, is the correction coefficient caused by the deflection angle of the anemometer, is the measured wind speed of the anemometer, θ is the angle generated between the mast and the vertical direction when the wind comes, c x is the air resistance coefficient of the anemometer, ρ is the air density at the measurement height of the UAV, s Lx is the projected area of the anemometer in the horizontal direction, T is the tension generated by the mast, m is the mass of the anemometer, is the acceleration at the rod end measured by the acceleration sensor.

2. The measuring device according to claim 1, characterized in that: When the initial measured wind speed of the target measurement point is lower than the preset wind speed threshold, the target measurement point is in the low wind speed area; when it is higher than or equal to the preset wind speed threshold, the target measurement point is in the high wind speed area.

3. The measuring device according to claim 2, characterized in that: The value range of the preset wind speed threshold is: [4, 6] m / s.

4. The measuring device according to claim 1, characterized in that: The swaying speed of the rod end It is calculated according to the following formula: In the formula, is the acceleration of the rod end measured by the acceleration sensor at the end of the rod, and t represents time.

5. The measuring device according to claim 1, characterized in that: The velocity generated by the rotation of the wing downward when the drone hovers It is calculated according to the following formula: In the formula, P is the output power of the drone, M is the total mass of the drone and the pole, and g is the acceleration due to gravity, with the direction being vertically downward.

6. The measuring device according to claim 1, characterized in that: The pole is a carbon fiber pole, and the value range of its length is: [80, 120] cm.

7. The measuring device according to claim 1, characterized in that: The measuring device is a measuring device for the urban canopy wind field.

8. A system based on the measuring device according to any one of claims 1-7, characterized in that: It includes the measuring device and a computer. The computer is connected to the measuring device. When Scheme B is adopted, the computer uses the data collected by the measuring device to perform data calculations to obtain the wind speed of the target measurement point.

9. A wind field measurement method based on the measuring device according to any one of claims 1-7, characterized in that: It includes the following steps: First, identify whether the wind speed of the target measurement point belongs to the low wind speed area or the high wind speed area. If it belongs to the low wind speed area, adopt Scheme A; if it belongs to the high wind speed area, adopt Scheme B. Then, control the drone to fly until the measuring device reaches the target measurement point, and obtain the actual wind speed of the target measurement point according to Scheme A or Scheme B.

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