Dayu Doppler Flowmeter Applied to Sewage Pipeline Flow Monitoring in Anren Town, Jiande City, Hangzhou

　　  What kind of flow monitoring equipment should we choose for general stormwater and sewage pipelines?

Electromagnetic flowmeters can only measure full-pipe conditions. The reason why measurement results are unstable under non-full-pipe conditions is that a non-full-pipe state can be understood as an extreme case where the measured liquid medium contains a large number of air bubbles.

Stormwater and sewage pipelines are often in a non-full-pipe state, and only become full when it rains. So under such conditions, what is the most suitable flow measurement method? Currently, the most advanced technology in China is undoubtedly the Doppler ultrasonic flowmeter. For such stormwater and sewage pipelines, it can accurately monitor water level, flow velocity, flow rate, instantaneous flow, cumulative flow, water temperature, and other data. It can be refreshed in real time and is also very easy to install.

　　The Doppler ultrasonic flowmeter is a flow measurement instrument based on the acoustic Doppler effect principle. It uses ultrasonic transducers to detect flow velocity via ultrasonic waves. The measurement point is located in front of the probe, which does not disrupt the flow field. It offers high measurement accuracy and a wide range; it can measure both weak and strong currents; it has high resolution and fast response; it can measure instantaneous velocity as well as average velocity; the measurement is linear, and the velocity calibration curve is not prone to change; it has no mechanical rotating parts, so there are no issues with sediment blockage or entanglement by aquatic plants; the probe is rugged and durable, not easily damaged, and is easy to operate.