Investigating the Effects of Partial Deviation of Acoustic Doppler Velocimeter on Measured Flow Characteristics

Document Type : Research Paper

Authors

1 Department of Water Engineering, Faculty of Agriculture, Shahid Nahonar University of Kerman, Kerman, Iran

2 Department of Water Engineering, Faculty of Agriculture, Shahid Bahonar University of Kerman,, Kerman, Iran

Abstract

Acoustic Doppler Velocimeter is one of the most widely used devices in hydraulic laboratories for measuring 3D flow characteristics. The holder of these devices may be slightly deflected over time or during initial installation, and the ADV receivers may not be exactly parallel to the flume. This study investigates the effects of ADV deviation on measured values of flow characteristics. For this purpose, a technician has installed the ADV device on the flume. Partial deviations in both horizontal and vertical planes are measured accurately. Velocity profile was measured in the center of the channel. The results showed that 2 mm deviation in horizontal and vertical planes causes 240% and 67% error in measuring the transversal and vertical velocities, respectively. The effect of deviation on turbulence intensity is significant. Besides, this deviation causes 148% error in Reynolds shear stress measurements. A comparison between measured profiles and global distribution of different parameters shows big difference between them. Finally, the proposed equations to correct the instantaneous 3D velocities perform well and can be used as post-processing tool.

Keywords


Afzalimehr, H. and Anctil, F. (1998) Estimation of gravel-bed river flow resistance. Journal of Hydraulic Engineering, 124(10), 1054-1058.
Afzalimehr, H., Barahimi, M. and Sui, J. (2017) Non-uniform flow over cobble bed with submerged vegetation strip. Water Management, 172(2), 1-40.
Afzalimehr, H., Maddahi, M. R., Naziri, D. and Sui. J. (2019a) Effects of non-submerged boulder on flow characteristics – A field investigation. International Journal of Sediment Research, 34(2), 136-143.
Afzalimehr, H., Maddahi, M. R., Sui. J. and Rahimpour. M. (2019b) Impacts of vegetation over bedforms on flow characteristics in gravel-bed rivers. Journal of Hydrodynamics, 31, 986-998.
Bagheri, S. and Heidarpour, M. (2012) Characteristics of flow over rectangular sharp-crested side weirs. Journal of Irrigation and Drainage Engineering, 138(6), 541-547.
Chanson, H., Trevethan, M. and Aoki, S. (2008). Acoustic Doppler velocimetry (ADV) in small estuary: Field experience and signal post-processing. Flow Measurement and Instrumentation, 19, 307-313.
Demiral, D., Boes, R. M. and Albayrak. I. (2020) Effects of secondary currents on turbulence characteristics of supercritical open channel flows at low aspect ratios. Water, 12(11), 3233.
Dey, S., Sarkar, S. and Solari, L. (2011) Near-bed turbulence characteristics at the entrainment threshold of sediment beds. Journal of Hydraulic Engineering, 137(9), 945-958.
Fazel Najafabadi, E., Afzalimehr, H. and Sui, J. (2015) Turbulence characteristics of favorable pressure gradient flows in gravel-bed channel with vegetated walls. Journal of Hydrology and Hydromechanics, 63(2), 154-163.
Fazel Najafabadi, E., Afzalimehr, H. and Rowinski, P. M. (2018) Flow structure through a fluvial pool-riffle sequence – Case study. Journal of Hydro-environment Research, 19, 1-15.
Goring, D. G. and Nikora, V. I. (2002) Despiking Acoustic Doppler Velocimeter data. Journal of Hydraulic Engineering, 128(1), 117-126.
Keshavarzi, A. and Hamidifar, H. (2018) Kinetic energy and momentum correction coefficients in compound open channels. Natural Hazards, 92, 1859-1869.
Kraus, N. C., Lohrmann, A. and Cabrera, R. (1994) New acoustic meter for measuring 3D laboratory flows. Journal of Hydraulic Engineering, 120, 406-412.
Maddahi, M. R., Afzalimehr, H. and Rowinski, P. M. (2016) Flow characteristics over a gravel bedform: Kaj River case study. Journal of Acta Geophysica, 64(5), 1779-1796.
Mohajeri, S. H., Safarzadeh, A. and Salehi Neyshabouri, S. A. A. (2018) Importance of bed roughness in transversal variability of the flow patterns and bed shear stress due to secondary currents. Scientia Iranica, Transactions A: Civil Engineering, 25, 1956-1967.
Naderi, M., Afzalimehr, H. and Sohrabi, S. (2021) Investigation of three-parameter flow resistance model in coarse-bed rivers (case study: Deryuk River). Iranian Journal of Soil and Water Research, 52(5), 1423-1435. (In Farsi)
Nepf, H. M. (1999) Drag, turbulence, and diffusion in flow through emergent vegetation. Water Resources Research, 35(2), 479-489.
Nezu, I. and Nakagawa, H. (1993) Turbulence in open-channel flows. Rotterdam: IAHR-AIRH monograph series.
Nikora, V. and Goring, D. (2000) Flow Turbulence over fixed and weakly mobile gravel beds. Journal of Hydraulic Engineering, 126(9), 679-690.
Shahmohammadi, R., Afzalimehr, H. and Sui, J. (2018) Impacts of turbulent flow over a channel bed with a vegetation patch on the incipient motion of sediment. Canadian Journal of Civil Engineering, 45, 803-816.
Yalin, M. S. (1992) River mechanics. Oxford: Pergamon press Ltd.