Investigation of the Impacts of Submerged Vanes on Pressurized Flushing in Reservoirs

Document Type : Research Paper

Authors

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

2 Disaster Prevention Research Institute, Kyoto University, Kyoto. Japan

Abstract

Pressurized flushing is one of the techniques for evacuating sediments from reservoirs. In this study, the impact of submerged vanes on performance of pressurized flushing were investigated. For this purpose, submerged vanes with convergent, divergent and combined arrangements in three distances from the bottom outlet (), three middle distances () and three heights above the sediment bed () were used and the results were compared with the non structural test (reference test). The results showed that the submerged vanes by creating rotational flow and turbulence, enhanced the performance of flushing and also by evacuating much sediment below the bottom outlet, the amount of evacuated sediments increased in all experiments. As, in the convergent and divergent arrangements, the volume of evacuated sediments increased respectively 6.5 and 48 times compared to the non structural test. Also, in the combined arrangement with two-row divergent of submerged vanes, in 0.5, 0.3 and 1, the volume of flushing cone increased 51 times compared to reference test. Finally, by using a polynomial correlation with vane spacing, a non-dimensional equation for estimating the scour cone volume was proposed.

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Abdipor, A., Ahmadi, H. and shamsai, A. (2016). Investigation and evaluation of the effects of jet on the pressure flushing in hydropower reservoirs. Journal of Iranian Dam and Hydroelectric Powerplant, 2 (7), 35-45. (In Farsi)
Abdollahpour, M. and Hossein zadeh dalir, A. (2013). Effect of Semi-Cylinder Structure Position on Pressurized Flushing Efficiency of Reservoirs. Water and soil science journal, University of Tabriz, 23(2), 269-282. (In Farsi)
Abdolahpour, M. and Hossein zadeh dalir, A. (2016). Application of pile and
submerged vanes to remove sediments from dam reservoirs in pressurized flushing. Iranian water research journal, 9(19), 165-169. (In Farsi)
Ahadpour Dodaran, A. Park, S.K. Mardashti, A. and Noshadi, M. (2012). Investigation of dimension changes in under pressure hydraulic sediment flushing cavity in storage dams under the effect of localized vibrations in the sediment layers. International Journal of Ocean System Engineering, 2(2), 71-81.
Jalili, H. and Hossein zadeh dalir, A. (2012). Extend the vortex flow around the reservoirs sluice gate. Proceedings of the First International Conference on Dams and Hydropower, Tehran, IRAN, 1-13. (In Farsi)
Jenzer Althaus, J. M. I., Cesare, G. D. and Schleiss, A. J. (2015). Sediment evacuation from reservoirs through intakes by Jet-Induced flow. Journal of Hydraulic Engineering, 141(2), 04014078.
Madadi, M.R., Rahimpour, M. and Qaderi, K. (2016). Sediment flushing upstream of large orifices: An experimental study. Journal of Flow Measurement and Instrumentation, 52, 180-189.
Madadi, M.R., Rahimpour, M. &and Qaderi, K. (2017). Improving the Ppressurized flushing efficiency in reservoirs: an experimental study. Water Resources Management, 31(14), 4633–4647.
Mahtabi, G.H., Karimi, S. and Mohamadioun, M. (2018). Effect of the number of rows, height and arrangement of submerged vanes in flushing of dam reservoir. Journal of Water and Soil Conservation, 25(1), 285-296. (In Farsi)
Melville, B.W. (1997). Pier and abutment scour-an integrated approach. Journal of Hydraulic Engineering ASCE, 123(2), 125-136.
Mohammadi, M., Salmasi, F., Hossein zadeh dalir, A. and Arvanaghi, H. (2014). Experimental Investigation of the effect of a Semi-Cylinderical structure on increasing pressurized sediment flushing capacity in reservoirs of dams. Water and soil science journal, University of Tabriz, 24(2), 21-30. (In Farsi)
Morris, G. L. and Fan, J. (2009). Reservoir Sedimentation Handbook: Design and Management of Dams, Reservoirs, and Watersheds for Sustainable Use; New York, McGraw Hill, Electronic Version, pp: 784.
Odgaard, A. J. and Kennedy, J.F. (1983). River-Bend Bank Protection by submerged vanes. Journal of Hydraulic Engineering, ASCE, 109(8), 1161-1173.
Odgaard, A. J. and Wang, Y. (1991). Sediment management with submerged vanes, I: Theory. Hydraul. Eng. ASCE, 117(3), 267-283.
Odgaard, A. J. (2017). River Management with Submerged Vanes.  River System Analysis and Management, pp 251-261.
Ouyang, H. and Lai, J. (2006). Interaction between submerged vanes and its effects on transverse bed profile in river bend. The seventh international conference on hydro science and engineering, Philadelphia, USA, 10-13.
Shafai Bajestan, M., Khademi, Kh. and Khozeymehnezhad, H. (2015). submerged vane-attached to the abutment as scour countermeasure. Ain Shams Engineering Journal, 6, 775-783.Tigrek, S. and Aras, T. (2011). Reservoir Sediment Management. Taylor & Francis.
Soon-Keat, T., Guoliang, Y., Siow-Yong, L. and Muk-Chen. (2005). Flow structure and sediment motion around submerged vanes in open channel. Journal of Waterway, Port, Coastal and Ocean Engineering, ASCE, 131(3), 132-136.
Tafarojnoruz, A., Gaudio, R. and Calomino, F. (2012). Evaluation of Flow-Altering Countermeasures against Bridge Pier Scour. Journal of Hydraulic Engineering ASCE, 138, 297-305.
Tigrek, S. and Aras, T. (2011). Reservoir Sediment Management. Taylor & Francis.
Turkben, B. (2018). Experimental Study of Submerged Vanes in Intakes under Sediment Feeding Conditions. E3S Web of Conferences, 40, 03016, River Flow.
White, R. (2000). Flushing of Sediments from Reservoirs, ICOLD. World Register of Large Dams, HR Wallingford, UK.