How Does the DOF6000 Measure Flow in Partially Filled Pipes?

Many sewer systems and drainage pipelines operate under gravity rather than pressure. As a result, the pipe may only be partially filled, making conventional full-pipe flow meters unsuitable for some applications.

The Lanry DOF6000 open channel flow meter is designed for partially filled pipes, wastewater pipelines, culverts, and open channels. It combines ultrasonic Doppler velocity measurement with water depth measurement to calculate the actual flow rate.

The DOF6000 uses the area-velocity method:

The ultrasonic Doppler flow sensor measures liquid velocity using signals reflected by suspended particles or small gas bubbles. The instrument measures water depth and calculates the wetted area based on the configured pipe diameter or channel geometry.

When the water level changes, the wetted cross-sectional area changes accordingly. This allows the partially filled pipe flow meter to calculate flow under varying water levels.

The DOF6000 supports circular pipes from DN150 to DN6000 and suitable open channels wider than 200 mm, subject to the applicable configuration.

Typical applications include:

• [✓] Municipal sewage flow measurement
• [✓] Wastewater treatment plant monitoring
• [✓] Industrial wastewater discharge measurement
• [✓] Stormwater and drainage flow monitoring
• [✓] Culvert and gravity pipeline measurement
• [✓] River and stream flow monitoring

Before selecting an ultrasonic Doppler flow meter, confirm the pipe diameter or channel dimensions, minimum and maximum water depth, liquid characteristics, expected flow velocity, and installation conditions.