Doppler open channel flow monitoring system

1. Product introduction of Doppler open channel flow monitoring system

The Doppler open channel flow monitoring system, also known as the Doppler flow meter, is an automatic monitoring, unattended channel flow measurement device used to measure the liquid flow in channels that are not full or open to discharge. instrument. The FT-ML1 Doppler open channel flow monitoring system is mainly composed of four parts: Doppler current meter, data acquisition, communication network and software platform. The Doppler current meter is a sensor that measures the flow rate and flow rate of water in natural water bodies. Doppler flowmeter is divided into two parts: sensor and host.

The sensor has two transducers, one transmitting and one receiving. When the sensor is facing the direction of the flow, that is, under the premise of counter-flow measurement:

1. When the water flow is stationary, the received frequency is the same as the transmitting frequency.

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

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

When the sensor measures along the direction of water flow:

1. When the water flow is stationary, the received frequency is the same as the transmitting frequency.

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

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

From the above, the water flow rate and direction of the water flow can be calculated through hardware and software.

2. Working principle of Doppler open channel flow monitoring system

Product flow rate measurement is based on the Doppler effect. The probe emits a beam of ultrasonic waves obliquely upward. When the ultrasonic waves contact impurities or bubbles in the fluid, the reflected ultrasonic waves will produce a Doppler frequency shift Δf. The Doppler frequency shift Δf is proportional to the fluid. Flow velocity, the flow velocity V of the fluid can be measured by measuring the Doppler frequency shift Δf.

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

Q = V × S

Features

l Uses ultrasonic Doppler principle to measure flow velocity and measurement, with high accuracy and small environmental restrictions;

l The velocity area method is used to measure flow, without the need to build weirs and trenches, and the construction cost is low;

lHigh integration, supports simultaneous measurement of flow rate, liquid level, instantaneous flow, cumulative flow, and temperature;

l Comes with a temperature sensor to compensate for the impact of water temperature on the speed of sound;

l Built-in circular, rectangular, trapezoidal, triangular and other pipeline models for easy debugging;

lBionic appearance design effectively reduces garbage occlusion;

lLow power consumption design; operating current is less than 25mA; suitable for battery or solar power supply.

3. Parameter indicators of Doppler open channel flow monitoring system

4. How to use the Doppler open channel flow monitoring system

1. Installation requirements

Water quality requirements: According to the measurement principle, the water to be measured must contain certain tiny impurities or bubbles, but there should not be too many floating objects in the water to avoid interference.

Water flow pattern requirements: It should be installed downstream of a straight section with a fixed cross-section. 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 within this distance range There must be no overflow obstructions (such as sluices, weirs, etc.) to ensure a uniform and stable flow pattern in the front section of the probe.

2. Installation diagram

5. Introduction to Doppler Open Channel Flow Monitoring System Cloud Platform

1. CS architecture software platform supports direct observation on mobile phones and PC browsers without the need to install additional software.

2. Support multiple accounts and multiple devices to log in

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

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

5. Support SMS alarm and threshold setting

6. Support map display and view device information.

7. Support data curve analysis

8. Support data export table format

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

10.Support data post-processing function

11.Support external running of javascript scripts