ASSESSMENT OF FLOW CHARACTERISTICS ALONG THE HYDRAULIC PHYSICAL MODEL OF A DAM SPILLWAY
Abstract
Water flowing over a spillway has a very high kinetic energy because of the conversion of the entire potential energy to kinetic energy. This circumstance results in damage or significant erosion at the toes of the spillways, weir bed, and downstream of a river. To solve this problem, the water flow velocity must be minimised. Physical modelling was implemented to this conundrum in order to modify the current energy dissipating structure, the stilling basin, to enhance energy dissipation as much as achievable by downstream velocity reduction. Baffle blocks were adopted as the modification in this study because these are widely used to stabilize the jumps, shorten its length, and maximize energy dissipation. A selection of baffle arrangements was evaluated by positioning them in the stilling basin’s mid-span to identify the most effective outcome in minimizing downstream velocity. From the findings, it was clearly shown the arrangement of baffles blocks at the stilling basin impacts velocity reduction in various discharge cases. The formation of cross-waves was also assessed at the discharge channel at every discharge value with its relative distance from the sump and the width of the channel prior to the site. For discharge situations of 70.0 L/s and 100.0 L/s, modifications to the Type II stilling basin were recommended. Furthermore, constriction, expansion, or curvature should be avoided in chute spillways identical to the dam spillway to limit cross-wave generation and other unfavourable flow behaviours.
References
Rong, Y., Zhang, T., Peng, L., & Feng, P. (2019). Three-dimensional numerical simulation of dam discharge and flood routing in Wudu reservoir. Water, 11(10), 2157. https://doi.org/10.3390/w11102157
Razzak Al-Husseini, T. (2015). Experimental study of increasing energy dissipation on stepped spillway. Journal of Kerbala University, 11(1), 87-100.
Hayder, A. M., & Jafar, M. S. (2015). Investigation of energy dissipation in stepped spillway with semicircular steps treads. Asian Transactions on Engineering, 5(3), 1–5.
Ammar, H. K., Isam, M. A., & Zainab, T. (2016). Study the effect of spillway locations on the hydraulic properties of spillway. Ciência e Técnica Vitivinícola, 31(5), 90–106.
Nigam, U., Das, S., & Choudhury, M. R. (2016). Overview of energy dissipators and stilling basins with design aspects of hydraulic jump type energy dissipators. Conference Proc NCIET.
Abdel Aal, G. M., Sobeah, M., Helal, E., & El-Fooly, M. (2018). Improving energy dissipation on stepped spillways using breakers. Ain Shams Engineering Journal, 9(4), 1887–1896. https://doi.org/10.1016/j.asej.2017.01.008
Daneshfaraz, R., & Ghaderi, A. (2017). Numerical investigation of inverse curvature ogee spillway. Civil Engineering Journal, 3(11), 1146–1156. https://doi.org/10.28991/cej-030944
Gu, S., Ren, L., Wang, X., Xie, H., Huang, Y., Wei, J., & Shao, S. (2017). SPHysics simulation of experimental spillway hydraulics. Water, 9(12), 973. https://doi.org/10.3390/w9120973
Orekhov, G. (2018). Hydraulic spillways using the effect of interacting circulation currents. IOP Conference Series. Materials Science and Engineering, 365, 042023. https://doi.org/10.1088/1757-899x/365/4/042023
Hien, L. T. T. (2020). Study the flow over chute spillway by both numerical and physical models. In APAC 2019 Springer Singapore, 845–851. https://doi.org/10.1007/978-981-15-0291-0_116
Ghazi, B., Daneshfaraz, R., & Jeihouni, E. (2019). Numerical investigation of hydraulic characteristics and prediction of cavitation number in Shahid Madani Dam's Spillway. Journal of Groundwater Science and Engineering, 7(4), 323-332. https://doi.org/10.19637/j.cnki.2305-7068.2019.04.003
Nouri, M., Sihag, P., Salmasi, F., & Kisi, O. (2020). Energy loss in skimming flow over cascade spillways: Comparison of artificial intelligence-based and regression methods. Applied Sciences (Basel, Switzerland), 10(19), 6903. https://doi.org/10.3390/app10196903
Abbas, A. S., Alwash, H. H., & Mahmood, A. H. (2018). Effect of baffle block configurations on characteristics of hydraulic jump in adverse stilling basins. MATEC Web of Conferences, 162, 26–32. https://doi:10.1051/matecconf/201816203005
Chatila, J. G., & Jurdi, B. R. (2004). Stepped spillway as an energy dissipater. Canadian Water Resources Journal, 29(3), 147–158. https://doi.org/10.4296/cwrj147
Yang, C. S., Kao, S. -P. &., Lee, F. B., & Hung, P. -S. (2004). Twelve different interpolation methods: A case study of Surfer 8.0. In Proceedings of the XXth ISPRS Congress, 35, 778–785.
Li, Q., Li, L., & Liao, H. (2018). Study on the best depth of stilling basin with shallow-water cushion. Water, 10(12), 1801. https://doi.org/10.3390/w10121801
Ahmed, S. S., & Aziz, Y. W. (2018). Evaluation of hydraulic performance of Nazanin dam side channel spillway. Zanco Journal of Pure and Applied Sciences, 30(1), 62-69. https://doi.org/10.21271/ZJPAS.30.s1.7
Nunes, A. F. P. (2017). Computational modelling of skimming flow over stepped spillways with sidewall convergence.
Dehdar-Behbahani, S., & Parsaie, A. (2016). Numerical modeling of flow pattern in dam spillway’s guide wall. Case study: Balaroud dam, Iran. Alexandria Engineering Journal, 55(1), 467-473. https://doi.org/10.1016/j.aej.2016.01.006
Mahtabi, G., Chaplot, B., Azamathulla, H. M., & Pal, M. (2020). Classification of hydraulic jump in rough beds. Water, 12(8), 2249. https://doi.org/10.3390/w12082249
Copyright (c) 2022 UNIMAS Publisher
This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.
Upon acceptance of an article, the corresponding author on behalf of all authors will be asked to complete and upload the Copyright Transfer Form (refer to Copyright Issues for more information on this) alongside the electronic proof file.
Copyright Transfer Statement for Journal
1) In signing this statement, the author(s) grant UNIMAS Publisher an exclusive license to publish their original research papers. The author(s) also grant UNIMAS Publisher permission to reproduce, recreate, translate, extract or summarize, and to distribute and display in any forms, formats, and media. The author(s) can reuse their papers in their future printed work without first requiring permission from UNIMAS Publisher, provided that the author(s) acknowledge and refer the publication in the Journal.
2) For open-access articles, the author(s) agree that their articles published under UNIMAS Publisher are distributed under the terms of the Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License (CC BY-NC-SA 4.0) which permits unrestricted use, distribution, and reproduction in any medium, for non-commercial purposes, provided the original work of the author(s) is properly cited.
3) For subscription articles, the author(s) agree that UNIMAS Publisher holds the copyright or an exclusive license to publish. Readers or users may view, download, print, and copy the content, for academic purposes, subject to the following conditions of use: (a) any reuse of materials is subjected to permission from UNIMAS Publisher; (b) archived materials may only be used for academic research; (c) archived materials may not be used for commercial purposes, which include but not limited to monetary compensation by means of sale, resale, license, transfer of copyright, loan, etc.; and (d) archived materials may not be re-published in any part, either in print or online.
4) The author(s) are responsible to ensure their submitted work is original and does not infringe any existing copyright, trademark, patent, statutory right, or propriety right of others. The corresponding author has obtained permission from all co-authors prior to submission to the journal. Upon submission of the manuscript, the author(s) agree that no similar work has been or will be submitted or published elsewhere in any language. If the submitted manuscript includes materials from others, the authors have obtained permission from the copyright owners.
5) In signing this statement, the author(s) declare that the researches which they have conducted comply with the current laws of the respective country and UNIMAS Journal Publication Ethics Policy. Any experimentation or research involving humans or the use of animal samples must obtain approval from the Human or Animal Ethics Committee in their respective institutions. The author(s) agree and understand that UNIMAS Publisher is not responsible for any compensational claims or failure caused by the author(s) in fulfilling the above-mentioned requirements. The author(s) must accept the responsibility for releasing their materials upon request by Chief Editor or UNIMAS Publisher.
6) The author(s) should have participated sufficiently in the work and ensured the appropriateness of the content of the article. The author(s) should also agree that they have no commercial attachments (e.g. patent or license arrangement, equity interest, consultancies, etc.) that might pose any conflict of interest with the submitted manuscript. The author(s) also agree to make any relevant materials and data available upon request by the editor(s) or UNIMAS Publisher.
