1. Product Introduction

ML1 Open Channel Flow Monitoring System is mainly composed of four parts: Doppler flow meter, data acquisition, communication network and software platform. The Doppler flow meter is a sensor used to measure the flow rate and discharge of water in natural water bodies. The Doppler flow meter is divided into two parts: sensor and host.

The sensor has two transducers, one for transmitting and one for receiving. When the sensor is facing the direction of the flow, i.e. measuring upstream:

1. In the case of a stream of water at rest, the received frequency is the same as the transmitted frequency.

2. The faster the flow rate, the faster the frequency received by the sensor, which will be higher than the frequency emitted.

3. The slower the flow rate, the slower the frequency received by the sensor, but it will be higher than the frequency emitted.

Provided that the sensor is measuring with the flow of water:

1. In the case of a stream of water at rest, the received frequency is the same as the transmitted frequency.

2. The faster the flow rate, the faster the frequency received by the sensor, but it will be lower than the frequency emitted.

3. The slower the flow rate, the slower the frequency received by the sensor, but it will be lower than the frequency emitted.

From the above, the flow velocity and flow direction of the water flow can be calculated by hardware and software.

Second, Working Principle

Product flow rate measurement is based on the Doppler effect, the probe emits a beam of ultrasound obliquely upward, when the ultrasound encounters impurities or bubbles in the fluid, it will cause a Doppler frequency shift Δf in the reflected ultrasound, the Doppler frequency shift Δf is proportional to the flow rate of the fluid, and the flow rate V of the fluid can be measured by measuring the Doppler frequency shift Δf.

The product measures liquid level based on pressure sensor, and the cross-sectional area S of the fluid can be automatically calculated through the set channel parameters, based on the velocity area method, so the flow rate Q of the liquid can be measured.

Q = V × S

Product features

I adopt the principle of ultrasonic doppler to measure the flow rate, the measurement, accuracy is high, and the environmental restrictions are small;

lThe flow rate is measured by the speed-area method, without the need to build a weir slot, and the construction cost is low;

l High integration, supports the simultaneous measurement of flow rate, liquid level, instantaneous flow rate, accumulated flow rate, and temperature;

l is equipped with a temperature sensor to compensate the influence of water temperature on sound velocity;

It is embedded with a variety of pipeline models such as circles, rectangles, trapezoids, triangles, etc., and is convenient to debug;

l Bionic appearance design, effectively reduce the garbage blockage;

l Low power consumption design; working current less than 25mA; applicable to battery or solar power supply.

Three, Parameter Indicators

IV. Method of Use

1. Installation requirements

Water quality requirements: According to the measurement principle, the water body to be tested needs to contain a certain amount of small impurities or bubbles, but the floating matter in the water should not be too much to avoid interference.

Hydraulic conditions of the water body: It should be installed downstream of the straight section with a fixed cross section, and the length of the straight section is preferably 5-10 times the hydraulic radius of the channel (the longer the straight section, the higher the measurement accuracy), and there should be no obstacles to the flow (such as sluice gates, weirs, etc.) in this distance range, to ensure that the flow in front of the probe is uniform and stable.

5. Introduction to the Cloud Platform

1. CS architecture software platform, supports mobile phones, PC browsers to observe directly, no need for additional software installation.

2. Support multiple accounts, multiple devices login

3. Support real-time data display and historical data display dashboard

4. Cloud servers, cloud data storage, stable and reliable, easy to expand, load balancing.

5. Support SMS alarm and threshold setting

6. Support for map display, view device information.

7. Support data curve analysis

8. Support for data export in table format

9. Support data forwarding, HJ-212 protocol, TCP forwarding, http protocol, etc.

10. Support for data post-processing functions

11. Support for external JavaScript scripts