Time difference method open channel flow monitoring system

1. Product Introduction of Time Difference Method Open Channel Flow Monitoring System

The time-difference method open channel flow monitoring system is also called the open channel time-difference method flowmeter. The time-difference method open channel flow monitoring system is used to monitor the flow of rivers or open channels with relatively stable cross-sections. It solves the problem of difficulty in linking data between the sending and receiving ends of the measurement and the inability to measure the flow of wider open channels. question. The ultrasonic multi-layer transit time flow meter is a device suitable for open channel flow measurement developed based on the principle of "ultrasonic pipe flow meter" at home and abroad. By extending the design structure of the ultrasonic pipe flow meter, it is applied to open channel flow measurement. . It has a multi-layer flow measurement method and can distribute the transducer layer structure design according to the type of channel. By measuring the flow velocity of different water layers, the measurement accuracy of the flow measurement equipment is improved.

2. Components of open channel flow monitoring system using time difference method

The ultrasonic multi-layer transit time measurement system mainly consists of the following equipment:

1. Three pairs of flow rate sensors

3. An ultrasonic liquid level sensor

3. Collection system

4.Solar power supply system

5. Pole and bracket

3. Working principle of open channel flow monitoring system using time difference method

The ultrasonic transit time method uses an acoustic transit time velocity meter to measure flow. Its principle is to install one or more pairs of transducers on both sides of the river at a certain angle (usually 45 degrees) to the flow direction. One transducer emits ultrasonic waves, and the other transducer emits ultrasonic waves. A transducer receives ultrasonic waves (the ultrasonic transmission route is called the acoustic path), and the acoustic transit time velocity meter measures the ultrasonic transmission time difference in the forward and counterflow directions to calculate the average flow velocity of the measurement line, which can realize multi-layer flow velocity monitoring through data modeling. Calculate the average flow velocity in the form, and then calculate the instantaneous flow rate through the flow velocity area method.

4. Characteristics of monitoring stations of open channel flow monitoring system using time difference method

1.Measurement advantages:

1.1 It is developed based on the design standards and calibration specifications of ultrasonic pipeline flow meters. It has extremely high accuracy and stability, and the open channel measurement accuracy can reach more than 95%;

1.2 The flow meter is installed in the channel of the open channel river. It can be equipped with multi-layer transducers to measure the flow velocity of different layers in real time, and adopts multiple sampling of the flow velocity of different water layers;

1.3 Since this flow measurement system adopts a multi-layer sensor structure, a laminar flow velocity distribution model can be established after running for a period of time, that is, even if only one layer of sensors can still work normally, the system equipment can still work efficiently;

1.4 Adopt IP68 protection level: The magnetostrictive water level meter (or dual-stage magnetic encoding water level meter) and flow velocity transducer in this system all have IP68 protection standards. Even when the water potential in the channel is high and all equipment is submerged, it can still operate normally. Work;

1.5 Correctable: As time goes by and the channel structure changes, the accuracy of this system can be further corrected by manually calibrating the calibration parameters into the integrated calculator.

2. Installation method characteristics

2.1 Embedded structure: The multi-layer flow meter and water level meter are installed twice in the channel in an embedded manner, which does not block water and avoid the attachment of aquatic plants, floating objects, etc., greatly reducing the maintenance workload;

2.2 The number of transducer layers and height can be set according to the water level and elevation: Due to the diversity of channel structures, the transducer section sets the height accordingly according to the characteristics of the channel (such as: 0.3H, 0.6H, 0.9H three-layer structure);

2.3 No water blocking characteristics: The equipment adopts an embedded installation method, and there is almost no water head loss, water blocking, etc., which improves irrigation efficiency.

3.Interference factors

3.1 The equipment is suitable for open channels with a channel width within the range of 0-50 meters and a certain regular cross-section;

3.2 When the equipment is used in water systems with high sediment content, the measurement accuracy will be affected to a certain extent;

3.3 The equipment cannot monitor the siltation of the channel in real time. The siltation of the channel needs to be checked regularly and desilted or calibrated.

5. Technical parameters of open channel flow monitoring system using time difference method