Journal of New Approaches in Water Engineering and Environment
Scientific Journal

Numerical Investigation of Energy Dissipation in Baffled Piano Key Weirs

Document Type : Original Article

Authors

Ali Iranpour 1
Aslan Egdernezhad 2
Mohammad Heidarnejad 3

1 1M.Sc. Student, Department of Civil Engineering, Ahvaz Branch, Islamic Azad University, Ahvaz, Iran.

2 Assistant professor, Department of Water Sciences and Engineering, Ahvaz Branch, Islamic Azad University, Ahvaz, Iran.

3 Associate professor, Department of Water Sciences and Engineering, Ahvaz Branch, Islamic Azad University, Ahvaz, Iran.

https://doi.org/10.22034/nawee.2024.451817.1069
Abstract
This test was done in the hydraulic laboratory of Khuzestan Water and Electricity Organization. The flume used had a rectangular cross-section with a length of 7 meters and a width of 0.6 meters. The walls of the flume were 10 mm thick and made of glass. In this experiment, 10 flow rates (from 10 to 50 liters per second) were used in free flow mode in the flume. Three piano keyboard overflows with different baffles were used. Baffles were circular, pentagonal and cubic. The overflows were made of transparent plexiglass with a thickness of 5 mm. The numerical model of Flow3D software was used to check the amount of energy consumption and compare the baffles. The highest energy loss with increasing yc/H occurred in cubic, circular and pentagonal baffles, respectively. The highest energy loss with increasing yc/H is in cubic, circular and pentagonal baffles, respectively. The energy loss in cubic, circular and pentagonal baffles was 0.65, 0.62 and 0.61, respectively. Therefore, the best result happened in the cubic baffle. By changing the height of the baffles, it was observed that the highest energy loss was measured at a height of 2 cm and the lowest value was measured at a height of 1 cm. It is recommended to use cubic baffles for more energy loss in piano key overflows. The best shape and dimensions of the baffle for this work are cubic and 2 * 2 cm.

Keywords

Flow3D
energy loss
stair weirs
Weber number
Eslinger, K.R. Crookston, B.M., 2020. Energy Dissipation of Type a Piano Key Weirs. Water, 12(1), 1253. https://doi.org/10.3390/w12051253.
Farhadi, H., Karami Moghadam, M., Sabzevari, T. and Noroozpour, Sh., 2023. Study of relative energy dissipation of trapezoidal arced piano key weirs equipped with baffles. Water Supply, 23(1), 80. https://doi.org/10.2166/ws.2022.427. (In Persian).
Ghaderi, A. Abbasi, S., 2019. Numerical Investigation of Labyrinth Stepped Spillways Performance on Energy Dissipation of Skimming Flow. Iranian Hydraulic Association Journal of Hydraulics, 14(3), 16. https://doi.org/10.30482/jhyd.2019.135883.1303. (In Persian).
Hien, T.C.; Son, H.T. Khanh, M.H.T., 2006. Results of some piano keys weir hydraulic model tests in Vietnam. In: Proceedings of the 22nd Congress of ICOLD, Barcelona, Spain.
Ho Ta Khanh, M., Sy Quat. D., Xuan Thuy, D., 2011. PK weirs under design and construction in Vietnam (2010). Labyrinth and piano key weirs-PKW 2011, 225–232. London, CRC Press.
Kamaei abbasi, B., Khodashenas, S.R., Heidarnejad, M., 2018. Experimental study of Discharge Coefficient in Two-Cycle Piano Key Weirs. Iranian Journal of Irrigation and Drainage, 13(1), 10–20. Doi: 20.1001.1.20087942.1398.13.1.2.8. (In Persian).
Lempe´rie`re F., 2009. New Labyrinth weirs triple the spillways discharge. http://hydrocoop.org.
Lempérière, F., 2017. Dams Floods. Engineering, 3(1), 144–149. https://doi.org/10.1016/J.ENG.2017.01.018.
Lempérière, F. Ouamane, A., 2003. The piano keys weir: A new cost-effective solution for spillways. International Journal on Hydropower and Dams, (5), 144–149.
Machiels, O., Erpicum, S., Archambeau, P., Dewals, B., Pirotton, M., 2013. Parapet wall effect on piano key weir efficiency. J Irrig Drain Eng., 139(6): 506–511.
Merkel, J. Belzner, F., Gebhardt, M., Thorenz, C., 2018. Energy Dissipation Downstream of Labyrinth Weirs. 7th International Symposium on Hydraulic Structures. Aachen, Germany. https://doi.org/10.15142/T32D2V.
Qanavati, M., Sajjadi, S.M. Ahadiyan, J., 2019.The Effect of Height and First Roughness Distance on Energy Dissipation in Piano Key Weirs. Irrigation Sciences and Engineering (JISE), 42(2), 17–13. Sid. https://sid.ir/paper/217075/fa. (In Persian).
Ribeiro, M, L., Pfister, M., Schleiss, A, J., 2013. Overview of Piano Key weir prototypes and scientific model investigations. Labyrinth and Piano Key Weirs II, 273.
Roshangar, K., Majedi Asl, M., Taghi Alami, M. Shiri, J., 2017. Evaluating the effect of arc cycle angle changes on the discharge coefficient of arched concourse overflows and arched piano key. Iran water and soil research, 49(2), 341–351. https://doi.org/10/22059/ijswr.2018.231028.667658.
Roushangar, K. Akhgar, S., 2021. Numerical and Experimental Study of Wedge Elements Influence on Hydraulic Parameters and Energy Dissipation over Stepped Spillway in Skimming Flow Regime. Amirkabir Journal of Civil Engineering, 53(1), 41–44. https://doi.org/10.22060/ceej.2018.14587.5689. (In Persian)
Roushangar. K., Alami, M.T., Shiri, J. Majedi Asl, M., 2018. Evaluation Effect of Changing the Cycle Arc Angle on Discharge Coefficient of Arced Labyrinth and Arced Piano Key Weirs. Iranian journal of soil and water research. 49(2), 241–351. https://doi.org/10.22059/IJSWR.2018.231028.667658 (In Persian)
Safarzadeh, A. Noroozi, B., 2016. 3D Hydrodynamics of Trapezoidal Piano Key Spillways. International Journal of Civil Engineering. Published online. https://doi.org/10.1007/s40999-016-0100-8.
Silverstri, A., Erpicum, S., Archambeau, P., Dewals, B., Pirotton, M. 2013. Stepped spillway downstream of a Piano Key weir—Critical length of uniform flow. In: International Workshop on Hydraulic Structures, 99–107. Bundesanstalt fur, Wasserbau, Karlsruhe, Germany.
Singh, D. Kumar, M., 2022. Hydraulic Design Analysis of Piano Key Weirs: A Review. Arabian Journal for Science and Engineering. Published online. https://doi.org/10.1007/s13369-021-06370-4.
Tiwaria, H. Sharma, N., 2015. Developments to improve hydraulic competence of spillways. Interanational Conference On Water Resources, Coastal And Ocean Engineering, 4, 841–846.
Yarmohammadi, B. Ahadiyan, J., 2019. Experimental study of continues and discontinues parapet walls on piano key weir flow. Iranian water research journal, 13(2), 33–41. https://sid.ir/paper/159716/fa (In Persian)
Journal of New Approaches in Water Engineering and Environment
Volume 3, Issue 1
March 2024
Pages 55-70

Home

Guide for Authors

Submit Manuscript

Reviewers

Contact Us