Open Channel Flowmeters and Doppler Flowmeters Applied to Irrigation and Water Conservancy

As is widely known, rural water pricing reform originated from the No. 1 Central Document, aiming to implement the principle of "one pump, one meter; one household, one card; pay first, then use water" for agricultural water use. The purpose of charging for agricultural water is to enforce water conservation and ensure efficient use of water resources.

Since the South-to-North Water Diversion Project was fully completed and began delivering water in 2014, the diverted water has become the primary water source for over 140 million people across more than 40 large and medium-sized cities, including Beijing and Tianjin, and over 280 counties and urban districts. Therefore, in water conservancy projects under the comprehensive agricultural water pricing reform, due to water scarcity in various regions and in response to the South-to-North Water Diversion initiative, open channel flowmeters and Doppler flowmeters are often adopted in farmland irrigation projects to measure water flow.

Dayu Electronics is a high-tech enterprise specializing in ultrasonic instruments and transducers, with 15 years of R&D and production experience, a wide range of products, and extensive technical expertise.

Below, we introduce our flagship product: the compact Doppler velocimeter used in the ultrasonic Doppler flowmeter, which is the transmitting probe of the instrument.

1.1 Measurement Principle

The ultrasonic Doppler velocimeter operates based on the Doppler effect. The probe emits an ultrasonic beam obliquely upward into the fluid. As the ultrasound propagates through the fluid, which contains impurities such as bubbles or particles (assumed to move at the same velocity as the flow), the reflection of the ultrasound off these impurities causes a Doppler frequency shift Δf. This Doppler shift Δf is proportional to the flow velocity. By measuring Δf, the flow velocity can be determined.

1.2 Product Features

? Wide input voltage: 10.8VDC to 26.4VDC

? Compact size: self-transmitting and self-receiving mode greatly reduces structural dimensions

? Wide applicability: two tilt angle options available for broader field applications

? High ingress protection: IP68

? High resolution

? Easy installation

1.3 Model Classification

         Dayu Electronics' products mainly fall into four categories: industrial control instruments, industrial sensors, marine equipment, and ultrasonic transducers. Product application scenarios include: ultrasonic distance measurement, monitoring of water level / flow velocity / flow rate / sludge level / water depth, and underwater communication / positioning / obstacle avoidance.