DBPapers
DOI: 10.5593/SGEM2014/B31/S12.019

COMPARISON OF PROFILE VELOCITY DETERMINATION BY ADV MEASUREMENT AND BY TRACER EXPERIMENTS

R. Schugerl, R. Dulovicova, Y. Veliskova
Wednesday 1 October 2014 by Libadmin2014

References: 14th International Multidisciplinary Scientific GeoConference SGEM 2014, www.sgem.org, SGEM2014 Conference Proceedings, ISBN 978-619-7105-13-1 / ISSN 1314-2704, June 19-25, 2014, Book 3, Vol. 1, 143-150 pp

ABSTRACT
One of the basic information about hydrodynamics of a stream is its velocity profile. The paper deals with the average profile velocity determination in a stream by two different methods: ADV (Acoustic Doppler Velocimeter – FlowTracker) and tracer experiments (indicator method). The ADV - FlowTracker (SONTEK Company) measures the stream flow velocity by 2D or 3D probe and it is based on application of Doppler principle. Tracer experiments (indicator method) for determination of velocity is one of the alternatives of hydrologic methods. Field measurements were performed on the Malá Nitra stream, in the part of Veľký Kýr village (N+48° 10’ 50.02", E+18° 9’ 19.60"). Solution of sodium chloride was used as a tracer. Average profile velocity was determined in four profiles, in a straight and a curved reach of the Malá Nitra stream. The velocity was measured by both methods in the each cross-section profile. The profiles were established in various distances (first profile – 60 meters; second profile – 180 meters; third profile – 410 meters; fourth profile – 730 meters). The first and second profile was located in a straight part of the stream, the third and fourth profile was located in a curved part of the stream. In particular experiments the tracer was applied into different location along width of the stream: in the middle, on the left bank and on the right bank. The results indicated that the differences between velocities determined by ADV and indicator method increase with growing distance. In the case of indicator method the accuracy of velocity assessment depends on localisation of tracer along width of the stream. In spite of that, measurement results assessment shows that indicator method is not influenced by tracer localisation on the right or on the left bank.

Keywords: Acoustic Doppler Velocimeter, average profile velocity, indicator method, tracer experiment