Accurate Flow Measurement in Large Pipes

The ADFM® Pro20 from Teledyne Isco (USA) brings unparalleled flow measurement accuracy to large pipes and channels, delivering flow rate data within 2% of actual value, in flow depths up to 20 feet (6 m). Four (4) piezoelectric ceramics in the sensor emit short pulses along narrow acoustic beams pointing in different directions to measure velocity. A fifth ceramic mounted in the center of the sensor assembly, and aimed vertically, is used to measure the depth.

Each acoustic beam measures velocity at multiple points, known as bins, in the water column. The measured velocity data within each bin are very precise – to within 0.01 ft/s. This distribution of accurate velocity measurements is then used to determine the flow pattern over the entire cross-section of flow. Since the flow pattern and measured velocity distribution are dependent on each other, the ADFM’s advanced flow algorithms automatically adapt to changing hydraulic conditions within the pipe. This removes the need for in-situ calibration and insures accurate flow rate measurement over a host of different measurement environments and hydraulic conditions.

The ADFM enclosure houses the signal processing, data logging, and data output electronics. The enclosure is available as a NEMA 4X Box housing, suitable for wall or console mounting in permanent applications, and a NEMA 6P cylindrical housing for use in manholes or other “wet” environments.