Investigation of Relative Depth Effect on Flow Characteristics in Meandering Compound Channel

Document Type : Research Paper

Authors

1 Water Engineering Department, Ferdowsi University of Mashhad, Mashhad, Iran

2 Water Engineering Department, Ferdowsi University of Mashhad, , Mashhad, Iran

Abstract

One of the important aspects in describing river behavior is its curvature. The production of successive bends in natural rivers is an inevitable component of the process through which the river changes. Understanding the flow behavior in the interaction between the main channel and the floodplain, especially during floods, is necessary to protect soil and water structures. This study was conducted to better understand the hydrodynamics of the middle and turbulent flow in compound meandering channels. According to the natural conditions of most rivers, due to variation of discharge and depth ratios (flow depth in floodplain to flow depth in the main channel), in this study, a rectangular meander laboratory channel with a constant sinuosity 1.3 for different depth ratios of 0.35 and 0.55 was investigated. The results showed that the size of velocity components (u,v,w) at 0.35 relative depth was greater than 0.55, which  indicating higher vortex strength and interaction intensity between the main channel and floodplain at lower relative depth. Also, by investigating the secondary flows, the existence of clockwise and counterclockwise rotational eddy currents in the main channel and floodplains and the location of these currents were determined.

Keywords

Main Subjects

References

Chow, V.T. (1959). Open channel hydraulics. McGraw-Hill, New York.
Goring, D. G. and V. I. Nikora. (2002). Despiking acoustic doppler velocimeter data. Journal of Hydraulic Engineering, 128(1): 117–126.
Hagerman, J. R., and Williams, J. D. (2000). Meander Shape and the Design of Stable Meanders. In Proceedings American Water Resources Association, Specialty Conference, Anchorage, Alaska, April
Liu, C., Shan, Y., Liu, X., and Yang, K. (2015). Method for assessing discharge in meandering compound channels. In Proceedings of the Institution of Civil Engineers-Water Management, 169(1), 17-29.
Liu, C., Shan, Y., Liu, X., Yang, K. and Liao, H. (2016). The effect of floodplain grass on the flow characteristics of meandering compound channels, Journal of Hydrology, 542, 1-17.
Mohanty, P. K., Dash, S. S., and Khatua, K. K. (2012). Flow investigations in a wide meandering compound channel. International Journal of Hydraulic Engineering, 1(6), 83-94.‏
Mohanty, P.K., (2019). Flow and its distribution in wide meandering compound channels. Journal of Hydrology, 575,115-130
Nikubakht, E., Hamidifar, H., and Keshavarzi, A. (2018). Effect of Floodplain Non-submerged Vegetation on Bed Variation in Meandering Compound Rivers. Iranian journal of Ecohydrology, 5(2), 461-470. (In Farsi).
Pan, Y., Li, Z., Yang, K. and Jia, D., (2019). Velocity distribution characteristics in meandering compound channels with one-sided vegetated floodplains. Journal of Hydrology, 578, 124068.
Patra, K.C., Kar, S.K. and Bhattacharya, A.K., (2004). Flow and velocity distribution in meandering compound channels. Journal of Hydraulic Engineering, 130(5), 398-411
Prabir, K. M., Saine, S. D., and Khatua, K. K. (2012). Flow Investigations in a Wide Meandering Compound Channel. Journal of Hydraulic Engineering, 1(6), 83-94
Sellin, R. H. J., Ervine, D. A., and Willetts, B. B. (1993). Behaviour of meandering two-stage channels. Proceedings of the Institution of Civil Engineers-Water Maritime and Energy, 101(2), 99-111.‏
Shiono, K. and Knight, D. W. (1991). Turbulent open-channel flows with variable depth across the channel. Journal of fluid mechanics. 222, 617-646.
Shiono, K., and Muto, Y. (1998). Complex flow mechanisms in compound meandering channels with overbank flow. Journal of fluid mechanics, 376, 221-261
Shiono, K., Chan, T. L., Spooner, J., Rameshwaran, P., and Chandler, J. H. (2009). The effect of floodplain roughness on flow structures, bedforms and sediment transport rates in meandering channels with overbank flows: Part I. Journal of Hydraulic Research, 47(1), 5-19‏‏
Shiono, K., Spooner, J., Chan, T., Rameshwaran, P. and Chandler, J., (2008). Flow characteristics in meandering channels with non-mobile. Journal of Hydraulic Research, 46(1), 113-132
Tominaga, A., Nezu, I., Ezaki, K., and Nakagawa, H. (1989). Three-dimensional turbulent structure in straight open channel flows. Journal of hydraulic research, 27(1), 149-173.
Wahl, T.L. (2000). Analyzing ADV data using WinADV, ASCE Joint Conference on Water Resources Engineering and Water Resources Planning and Management, Minneapolis, Minnesota, USA, July 30-August 2.
Wormleaton, P.R., Sellin, R.H.J., Bryant, T., Loveless, J.H., Hey, R.D. and Catmur, S.E., (2004). Flow structures in a two-stage channel with a mobile bed. Journal of Hydraulic Research. 42(2), 145-162
Weiming, W. U., and Zhiguo, H. E. (2009). Effects of vegetation on flow conveyance and sediment transport capacity. International Journal of Sediment Research. 24(3), 247-259.
Xiao, Y., Wang, N., Liang, D., and Liu, J. (2018). Flow structures in trapezoidal compound channels with different side slopes of main channel. International Journal of Civil Engineering, 16(7), 823-835.‏
Zahiri A, Amini R and Kordi H (2013). Numerical simulation of velocity lateral distribution in meandering compound channels. Journal of Water and Soil Conservation, 19(3), 201-218. (In Farsi).
Iranian Journal of Soil and Water Research
Volume 51, Issue 8
October 2020
Pages 2111-2124

Files

Share

How to cite

Statistics