Flow measurements using an upward-looking Argonaut-SW
Doppler current meter

Craig Huhta

Doppler velocity sensors have become increasingly common for flow monitoring in open channels. The most commonly used configurations are side mounted sensors that measure velocity at a single depth within the water column. Side mounted systems offer a number of advantages, including easy installation and maintenance. Their limitations include sites with variable water level or stratified flow, and the difficulty in producing a theoretical flow calculation based on velocity and level data.

We describe development and use of a bottom mounted Argonaut-SW Doppler current meter that is capable of flow measurements in channels with water level from 0.2 m to 4 m in depth. The meter provides a vertically integrated velocity measurement. This measurement configuration may provide an improved index velocity in complicated flow regimes, including highly variable water levels and stratified flow. It also provides improved performance for theoretical flow calculations, which are important in smaller channels where an index calibration may not be practical. The sensor is also intended for use in large pipes with diameter from 0.3 to 4 m.

This paper describes the sensor configuration, preliminary specifications and theoretical flow models used to calculate open channel and flow in partially and completely full pipes. Flume tests demonstrate good agreement with independent measurements.

Topic:
River Flow and Transport Measurement Techniques