Acoustic doppler velocimeter
From BAWiki
Definition
A device used to make ultrasonic measurements of flow velocities. ADVs are smaller than ADCPs and are used both for field and laboratory measurements. Contrary to ADCPs the measuring beams concentrate on a single spot (i.e. a very small measurement volume), thus immediately delivering results for this particular spot.
Synonyms
Abbreviations
ADV
Source
Guideline Upstream Fishways on German Federal Waterways (AH FAA), Bundesanstalt für Wasserbau (BAW) und Bundesanstalt für Gewässerkunde (BfG), Version 2.0, 26/06/2015 (retrieved 10.05.2017)