Comparison Of Adv And Piv Measurements In Open Channel Flows

To test the applicability of ADV, two techniques (ADV and PIV) have been applied for simultaneous measurement of an open channel flow. Comparison of the results (time-averaged velocity, turbulence intensity, Reynolds stress, and power spectra) reveals significant difference in the performance of PIV and ADV. For the ADV measurement in particular, the sampling frequency exerts little influence on the time-averaged velocity, and there exists a "sweet point', i.e., a 1cm sub-region of the overall 3cm profiling scope beyond which turbulent parameters cannot be correctly quantified. Thus, the ADV measurements in open channel flow need to be carefully evaluated in order to properly describe turbulent characteristics. (C) 2016 The Authors. Published by Elsevier Ltd.