|WORLD METEOROLOGICAL ORGANIZATION||
|Explanation of the criteria for classification and numbering of components||
|Explanation of the dates on the component's description|
ACOUSTIC CURRENT MEASUREMENT SYSTEM
1. Purpose and objectives
discharge, particularly in small or middle rivers.
Transducer units are placed on both sides of the current and ultrasonic pulses are transmitted between them on a diagonal path. The difference in travel time in both directions is a measure of the flow velocity, independent of the speed of sound in the water. The measured velocity is combined with the water depth and width to give the discharge.
The system is fully automatic and provides accurate measurements with a high reliability. The continuous measurements contribute to safety from natural disasters or accidents and the output can be used for multiple purposes. Conditions of abnormal sound propagation are detected.
to 4 m/s in either direction can be measured.
(flow rate) and water level signals.
The flow rate
and water level are available as BCD signals or analogue signals
(0 to 5 V, 4 to 20 mA), for telemetry or recording on site.
5. Operational requirements and restrictions
Except for civil engineering works necessary for construction of the facilities to install this system, the number of professional staff needed for its installation, operation and maintenance is four (4) at least.
Ambient temperature is 0 to +40 °C for the transducer and -10 to +40 °C for the coder with humidity below 90 %, non condensing.
The width of
the channel must be less than 30 m. Wider channels can
be measured with multiple parallel instruments. A site survey,
prior to installation, is needed to decide the design.
6. Form of presentation
and specifications of the system and home page are available at
7. Operational experience
The system has
been in use since 1981 and is now installed at more than 60 sites
8. Originator and technical support
10. Conditions on use
The hardware is for sale.
|(First entered: 1 JAN 93||
Last updated: 21 APR 00)