The Impact of Vegetation on ohe Characteristics of the Flow in an Inclined Open Channel Using the Piv Method
Journal of Water Resources and Ocean Science
Volume 1, Issue 1, December 2012, Pages: 1-8
Received: Dec. 15, 2012;
Published: Dec. 30, 2012
Views 4221 Downloads 204
Keramaris Evangelos, Department of Civil Engineering, Division of Hydraulic and Environmental Engineering, University of Thessaly, Pedion Areos, Volos, Greece
In this study, the impact of vegetation on the characteristics of the flow in an inclined open channel is studied experimentally using a Particle Image Velocimetry (PIV). This optical method of fluid visualization is used to obtain in-stantaneous velocity measurements related properties in the fluids. For the simulation of vegetated bed, flexible vegetation with grass with different height (2.5 cm and 5 cm) with the same porosity (ε=0.75) were used. These conditions can be commonly found in systems with sediment transport. Twenty-four (24) experiments were conducted, twelve (12) with the flexible vegetation of 2.5 cm and twelve (12) with the flexible vegetation of 5 cm. The slope of the channel was kept equal to S=2‰, S=4‰ and S=6‰. The experiments were conducted in the laboratory of Hydraulics in the department of Civil Infrastructure Engineering of Alexander Technological Educational Institute of Thessaloniki, Greece. The channel has a length of 6.5 m, width of 7.5 cm and height of 25 cm. The impact of the channel slope, the vegetation height, the vegetation length and the relative vegetation depth on the characteristics of the flow is studied. Measurements of velocity were taken for horizontal channel slope at different heights using the PIV. Results show that the bed type can significantly influence the characteristics of the flow.
The Impact of Vegetation on ohe Characteristics of the Flow in an Inclined Open Channel Using the Piv Method, Journal of Water Resources and Ocean Science.
Vol. 1, No. 1,
2012, pp. 1-8.
Beavers, G. S., Joseph, D. D., Boundary Conditions at a Naturally Permeable Wall, J. Fluid Mech., 30(1), 197–207, 1967.
Bigillon, F., Nino, Y., and Garcia, M.H., Measurements of turbulence characteristics in an open-channel flow over a transitionally-rough bed using particle image velocimetry. Experiments in Fluids, 41 (6), 857-867, 2006.
Carollo, F.G., Ferro, V. and Termini, D., Flow resistance law in channels with flexible submerged vegetation, J. of Hydraulic Engineering, 131(7), pp. 554-564, 2005.
Chan, H.C., Leu, J.M., Lai, C.J. and Yafei Jia, Turbulent flow over a channel with fluid-saturated porous bed, Journal of Hydraulic Engineering, ASCE, vol. 133, no. 6, pp 610-617, 2007.
Jarvela, J., Effect of submerged flexible vegetation on flow structure and resistance, J. of Hydrology, 307, pp. 233-241, 2005.
Pechlivanidis G., Keramaris E., Pechlivanidis I., Measurements of Turbulent Characteristics in an Open Channel Using PIV (Particle Image Velocimetry), Global Nest Journal, Volume 14 (3), pp. 378-385, 2012.
Poulikakos, D., Kazmierczak, M., Forced Convection in a Duct Partially Filled with a Porous Material, J. of Heat Transfer, 109, pp. 653–662, 1987.
Prinos, P., Sofialidis D., Keramaris E., Turbulent flow over and within a porous bed, Journal of Hydraulic Engineering, ASCE, vol. 129, pp. 720-733, 2003.
Stephan, U., Gutknecht, D., Hydraulic resistance of submerged flexible vegetation, Journal of Hydrology, vol. 269, (1/2), pp. 27-43, 2002.
Roussinova, V., Shinneeb, A-M. and Balachandar, R., Investigations of fluid structures in a smooth open-channel flow using proper orthogonal decomposition, J. of Hydraulic Engineering, 136(3), pp. 143-154, 2010.
Wilson, C.A.M.E, Stoesser, T., Bates, P.D. and Batemann Pinzen, A., Open channel flow through different forms of submerged flexible vegetation, J. of Hydraulic Engineering, 129(11), pp. 847-853, 2003.