Shallow lake surface flow velocity measuring device

Abstract

The utility model provides a shallow lake surface flow velocity measuring device, which relates to the field of hydrological survey and comprises a waterproof shell, the waterproof shell is composed of a top cover and a bottom shell, a GPRS / satellite data communication antenna is arranged in the middle of the top surface of the top cover, a solar panel is arranged on the bottom surface of the top cover, and a buoy partition plate is arranged on the lower portion of an inner cavity of the bottom shell. A frequency offset resolving module, a satellite positioning module, a GPRS / satellite data communication module and a storage battery are integrated on the top face of the buoy partition plate, and an acoustic Doppler transducer device is installed at the bottom of the buoy partition plate. Through the integrated design, the wind field influence is small when the lake water surface flow velocity is measured, the flow measurement precision is improved, the device can be used for researching the influence effect of the wind field on the lake surface flow in a large shallow lake, real verification data is provided for lake flow field numerical simulation, and the device is especially suitable for water diversion in lake water diversion engineering. A basis is provided for evaluating a water transfer project effect and analyzing influences on lake and bay hydrology, water ecology and the like by tracking water flow in real time, and the method can also be used for monitoring the water flow velocity under emergency conditions such as flood.

Description

Technical Field

[0001] This utility model relates to the field of hydrological measurement technology, and in particular to a device for measuring surface flow velocity in shallow lakes. Background Technology

[0002] For large, shallow lakes, wind-driven currents are the dominant form of flow field. Surface flow velocity directly reflects the dynamic influence of wind-driven currents, making surface flow monitoring crucial for lake aquatic ecology and water management assessments. Currently, there are two main methods for monitoring surface flow velocity: fixed-point and drift-based methods. Measurement equipment mainly includes surface buoys, acoustic Doppler current profilers (ADCPs), radio current meters, and non-contact microwave current meters. Fixed-point equipment can only measure flow velocity at fixed points, and its installation, use, and maintenance are inconvenient. Surface buoys, as the primary device for measuring surface flow velocity, are widely used in lake flow field monitoring. Currently, GNSS (Global Navigation Satellite System) positioning technology is often used to calculate flow velocity. This technology relies on the positioning and timing accuracy of GNSS, but currently, GNSS positioning accuracy only reaches the centimeter level, and its vertical elevation accuracy is inferior to its horizontal accuracy. For inland lakes with low flow velocities, the positioning accuracy, especially elevation accuracy, still needs further improvement. Some designs integrate ADCP (Advanced Diode Probe) into buoys to measure surface water velocity, but these are limited by the ADCP's blind zone and cannot effectively measure near-surface water velocity. Therefore, this invention designs a drifting buoy for measuring surface water velocity in lakes based on the acoustic Doppler effect. The buoy acts as a moving wave source, with a transducer emitting ultrasonic waves towards the bottom. The buoy's moving speed is calculated based on the received Doppler frequency deviation effect, and by considering the buoy's water-following behavior, the surface water velocity of the lake can be obtained. Utility Model Content

[0003] To address the aforementioned problems, this utility model discloses a shallow lake surface flow velocity measurement device, which can obtain high-precision lake surface flow velocity data in real time.

[0004] The specific plan is as follows:

[0005] A surface current velocity measurement device for shallow lakes includes a waterproof housing composed of a top cover and a bottom shell. The top cover is transparent and has a GPRS / satellite data communication antenna in the center of its top surface. A solar panel is attached to the bottom surface. A buoy partition is supported in the lower part of the inner cavity of the bottom shell. The top surface of the buoy partition integrates a frequency offset calculation module, a satellite positioning module, a GPRS / satellite data communication module, and a battery. Three non-vertically downward emitting acoustic Doppler transducers with different directions are installed at the bottom. The acoustic Doppler transducers are connected to the frequency offset calculation module. The frequency offset calculation module, the satellite positioning module, and the GPRS / satellite data communication antenna are connected to the GPRS / satellite data communication module. The battery powers the acoustic Doppler transducers, the satellite positioning module, and the GPRS / satellite data communication module. The solar panel is connected to the battery for charging.

[0006] Furthermore, the top cover and bottom cover of the waterproof housing are connected by a sealing ring, and the bottom cover is a hemispherical shape with an opening at the top.

[0007] Furthermore, a float counterweight is also installed on the buoy partition. The float counterweight is a hollow cylindrical structure and is divided into several empty compartments for filling with sandbags and other counterweights.

[0008] Furthermore, the acoustic Doppler transducer device is an HH30 type transceiver transducer with an operating frequency of 20kHz to 40kHz. It receives echoes from three directions through three transceiver probes, calculates the frequency offset through the frequency offset calculation module, converts them into three sub-velocities, and finally synthesizes them into the flow velocity of the specified coordinate system. The data is then transmitted to the data receiving and display terminal through the GPRS / satellite data communication module.

[0009] Furthermore, the frequency offset calculation module consists of a digital signal processing (DSP) module, an analog-to-digital converter (ADC) module, an FPGA data storage unit, and an external communication interface. It is used to calculate the frequency offset between the transmitted signal and the underwater reflected and received signal. The DSP module is a TMS326678 chip, the ADC module is an AD9257, the FPGA data storage unit connects the DSP module and the ADC module, and its external communication interface is an MSP430.

[0010] Furthermore, the satellite positioning module is a NEO-6M satellite positioning chip, which is used to send positioning information to a data receiving and display terminal via a GPRS / satellite data communication module to track the location in real time.

[0011] Furthermore, the GPRS / satellite data communication module is used to receive data from the frequency offset calculation module and the satellite positioning module, and transmit the data to the data receiving and display terminal via the GPRS / satellite data communication antenna. The GPRS is an industrial-grade RDT-G501 ​​embedded GPRS DTU module, and the satellite data communication is an FB5310 small 5W Beidou-3 RDSS transceiver module.

[0012] The beneficial effects of this application are as follows: through integrated design, the influence of wind field on the surface flow velocity of lake water is reduced, thus improving the accuracy of flow measurement. It can be used to study the impact of wind field on the surface flow of large shallow lakes, providing real verification data for numerical simulation of lake flow field. In particular, when water diversion projects are implemented in lakes, real-time tracking of water flow provides a basis for evaluating the effect of water diversion projects and analyzing their impact on lake bay hydrology and water ecology. It can also be used for monitoring water flow velocity in emergency situations such as floods. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the present invention.

[0014] Figure 2 This is a schematic diagram of the data transmission principle of this utility model.

[0015] List of reference numerals in the attached diagram:

[0016] 1-Waterproof shell, 2-Float counterweight, 3-Acoustic Doppler transducer device, 4-Frequency offset calculation module, 5-Satellite positioning module, 6-GPRS / satellite data communication module, 7-Battery, 8-Solar panel, 9-Sealing ring, 10-Buoy bulkhead, 11-GPRS / satellite data communication antenna, 12-Data receiving and display terminal. Detailed Implementation

[0017] The present invention will be further explained below with reference to the accompanying drawings and specific embodiments. It should be understood that the following specific embodiments are only used to illustrate the present invention and are not intended to limit the scope of the present invention.

[0018] As shown in the figure, this utility model provides a surface current velocity measurement device for shallow lakes, including a waterproof housing 1. The waterproof housing 1 consists of a top cover and a bottom shell arranged vertically. The top cover is transparent, and a GPRS / satellite data communication antenna 11 is provided in the center of its top surface. A solar panel 8 is attached to the bottom surface. A buoy partition 10 is supported in the lower part of the inner cavity of the bottom shell. The top surface of the buoy partition 10 integrates a frequency offset calculation module 4, a satellite positioning module 5, a GPRS / satellite data communication module 6, and a battery 7. Three non-vertically downward emitting acoustic Doppler transducer devices 3 with different directions are installed at the bottom. The acoustic Doppler transducer devices 3 are connected to the frequency offset calculation module 4. The frequency offset calculation module 4, the satellite positioning module 5, and the GPRS / satellite data communication antenna 11 are connected to the GPRS / satellite data communication module 6. The battery 7 is used to power the acoustic Doppler transducer devices 3, the satellite positioning module 5, and the GPRS / satellite data communication module 6. The solar panel 8 is connected to the battery 7 for charging.

[0019] The working principle is as follows: The acoustic Doppler transducer emits ultrasonic waves into the water. These waves are reflected from the lake bottom and received by the transducer. During the movement of the measuring device, a frequency deviation is generated between the emitted sound source and the received ultrasonic echo. The speed of the measuring device is calculated based on the relationship between the frequency deviation and the device's movement speed. With the help of a counterweight module, the density of the measuring device is changed, causing it to levitate on the water surface. A satellite positioning module tracks the device's position in real time. A GPRS / satellite data communication module transmits the speed calculated by the frequency deviation module and the GNSS satellite positioning data to a data receiving and display terminal. Since the acoustic Doppler transducer acquires the velocity in the direction of the sound wave, at least three sets of acoustic transducers are used to acquire the velocities in three directions to obtain the three-dimensional velocity of the floating body. The final velocity of the floating body is then synthesized. Based on the principle of water-body following, the velocity of the floating body is used to replace the surface current velocity.

[0020] In this embodiment, the top cover and bottom shell of the waterproof housing 1 of the measuring device are connected by a sealing ring 9, and the bottom shell is a hemispherical shape with an opening at the top.

[0021] In this embodiment, a float counterweight 2 is also installed on the buoy partition 10 of the measuring device. The float counterweight 2 is a hollow cylindrical structure divided into several empty compartments for filling with sandbags or other counterweights. This ensures that the center of gravity of the float is at the bottom of the float, increasing the stability of the float and minimizing the impact of wind.

[0022] In this embodiment, the acoustic Doppler transducer device 3 of the measuring device is an HH30 type transceiver transducer with an operating frequency of 20kHz to 40kHz. The lower part is made of sound-transparent material, and the upper part is a cylinder. A counterweight connected to the outer periphery of the top ensures that most of the shell is underwater. It receives echoes from three directions through three transceiver probes, calculates the frequency offset through the frequency offset calculation module 4, converts it into three sub-velocities, and finally synthesizes them into a flow velocity in a specified coordinate system. The data is then transmitted to the data receiving and display terminal 12 via the GPRS / satellite data communication module 6.

[0023] In this embodiment, the frequency offset calculation module 4 of the measuring device consists of a digital signal processing (DSP) module, an analog-to-digital converter (ADC) module, an FPGA data storage unit, and an external communication interface. It is used to calculate the frequency offset between the transmitted signal and the underwater reflected and received signal. The DSP module is a TMS326678 chip, the ADC module is an AD9257, the FPGA data storage unit connects the DSP module and the ADC module, and its external communication interface is an MSP430.

[0024] In this embodiment, the satellite positioning module 5 of the measuring device is a NEO-6M satellite positioning chip, which is used to send positioning information to the data receiving and display terminal 12 through the GPRS / satellite data communication module 11 to track the location in real time.

[0025] In this embodiment, the GPRS / satellite data communication module 6 of the measuring device is used to receive data from the frequency offset calculation module 4 and the satellite positioning module 5, and transmit the data to the data receiving and display terminal 12 through the GPRS / satellite data communication antenna 11. The GPRS is an industrial-grade RDT-G501 ​​embedded GPRS DTU module, and the satellite data communication is an FB5310 small 5W Beidou-3 RDSS transceiver module.

[0026] In this embodiment, the display terminal 12 is a regular PC.

[0027] In this embodiment, the solar panel 8 uses an 18V flexible solar panel.

[0028] The technical means disclosed in this utility model are not limited to those disclosed in the above embodiments, but also include technical solutions composed of any combination of the above technical features. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principle of this utility model, and these improvements and modifications are also considered within the scope of protection of this utility model.

Claims

1. A device for measuring surface flow velocity in shallow lakes, characterized in that: The system includes a waterproof housing (1), which consists of a top cover and a bottom shell. The top cover is transparent and has a GPRS / satellite data communication antenna (11) in the middle of its top surface. A solar panel (8) is attached to the bottom surface. A buoy partition (10) is supported in the lower part of the inner cavity of the bottom shell. The top surface of the buoy partition (10) integrates a frequency offset calculation module (4), a satellite positioning module (5), a GPRS / satellite data communication module (6), and a battery (7). Three non-vertically downward emitting acoustic Doppler transducer devices (3) with different directions are installed at the bottom. The acoustic Doppler transducer devices (3) are connected to the frequency offset calculation module (4), the satellite positioning module (5), and the GPRS / satellite data communication module (6). The communication antenna (11) is connected to the GPRS / satellite data communication module (6). The battery (7) is used to power the acoustic Doppler transducer device (3), the satellite positioning module (5) and the GPRS / satellite data communication module (6). The solar panel (8) is connected to the battery (7) to charge it. The acoustic Doppler transducer device (3) is an HH30 transceiver transducer with a working frequency of 20kHz to 40kHz. It receives echoes from three directions through three transceiver probes, calculates the frequency offset through the frequency offset calculation module (4), converts it into three sub-velocities, and finally synthesizes them into the velocity of the specified coordinate system. The data is then transmitted to the data receiving and display terminal (12) through the GPRS / satellite data communication module (6).

2. The shallow lake surface flow velocity measuring device according to claim 1, characterized in that: The top cover and bottom shell of the waterproof housing (1) are connected by a sealing ring (9), and the bottom shell is a hemispherical shape with an opening at the top.

3. The shallow lake surface flow velocity measuring device according to claim 1, characterized in that: The buoy partition (10) is also equipped with a buoy counterweight (2), which is a hollow cylindrical structure and divided into several empty compartments for filling counterweights.

4. The shallow lake surface flow velocity measuring device according to claim 1, characterized in that: The frequency offset calculation module (4) consists of a digital signal processing (DSP) module, an analog-to-digital converter (ADC) module, an FPGA data storage module, and an external communication interface. It is used to calculate the frequency offset between the transmitted signal and the underwater reflected and received signal. The DSP module is a TMS326678 chip, the ADC module is an AD9257, the FPGA data storage module connects the DSP module and the ADC module, and its external communication interface is an MSP430.

5. The shallow lake surface flow velocity measuring device according to claim 1, characterized in that: The satellite positioning module (5) is a NEO-6M satellite positioning chip, which is used to send positioning information to the data receiving and display terminal (12) through the GPRS / satellite data communication module (6) to track the location in real time.

6. The shallow lake surface flow velocity measuring device according to claim 1, characterized in that: The GPRS / satellite data communication module (6) is used to receive data from the frequency offset calculation module (4) and the satellite positioning module (5), and transmit the data to the data receiving and display terminal (12) through the GPRS / satellite data communication antenna (11). The GPRS is an industrial-grade RDT-G501 ​​embedded GPRS DTU module, and the satellite data communication is an FB5310 small 5W Beidou-3 RDSS transceiver module.

Images