Premium
Three‐dimensional measurement of river channel flow processes using acoustic doppler velocimetry
Author(s) -
Lane S. N.,
Biron P. M.,
Bradbrook K. F.,
Butler J. B.,
Chandler J. H.,
Crowell M. D.,
McLelland S. J.,
Richards K. S.,
Roy A. G.
Publication year - 1998
Publication title -
earth surface processes and landforms
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.294
H-Index - 127
eISSN - 1096-9837
pISSN - 0197-9337
DOI - 10.1002/(sici)1096-9837(199812)23:13<1247::aid-esp930>3.0.co;2-d
Subject(s) - acoustic doppler velocimetry , velocimetry , doppler effect , acoustics , flow velocity , flow (mathematics) , geology , flow measurement , channel (broadcasting) , acoustic doppler current profiler , orientation (vector space) , particle image velocimetry , current (fluid) , laser doppler velocimetry , mechanics , physics , geometry , computer science , turbulence , telecommunications , medicine , blood flow , oceanography , mathematics , astronomy
This paper describes and assesses: (i) the use of a new instrument for the determination of three‐dimensional flow velocities in natural rivers, the acoustic Doppler velocimeter (ADV); and (ii) a method for positioning and orienting such measurements relative to a single local coordinate system to relate flow velocity vectors with the bed and water surface. The ADV uses the Doppler shift principle to measure the velocity of small particles, assuming to be moving at velocities similar to the fluid. Velocity is resolved into three orthogonal components, and measured in a volume 5 cm below the sensor head, minimizing interference of the flow field, and allowing measurements to be made close to the bed. A simple method for positioning and orienting the instrument using digital tacheometry is described, and is used to obtain velocity measurements concurrently with measurements of both bed and water surface topography. The paper includes a preliminary field assessment of the ADV by comparing velocity profiles with those generated from Marsh McBirney electromagnetic current meters, and a full field assessment of the position and orientation methodology. These results suggest that the recommended methods in combination with an ADV are able to provide reliable mean three‐dimensional velocity field information and accurate bed and surface topography. Copyright © 1998 John Wiley & Sons, Ltd.