Volume 6 , Issue 1 , PP: 22-33, 2023 | Cite this article as | XML | Html | PDF | Full Length Article
Manal Gad 1 * , Zidan A. R. 2 , ElGamal M .A. 3 , Abd-Allah M. G. 4
Doi: https://doi.org/10.54216/IJBES.060102
A series of laboratory experiments was performed in order to investigate momentum and kinetic energy correction coefficients in compound transitions of rectangular channel. Also, In this study, the influence of several independent factors on the kinetic energy and momentum correction coefficients that are connected to the characteristics of the channels transitions is investigated. The Reynolds number varied between 2145.8 and 14388.14. Kinetic energy and momentum correction coefficients, α and β, were computed for different models by using two methods. The first one was based on the calculation of ε and the second method was based on dividing the cross section into slides and using the corresponding velocity for each slides. The results of the present study show that the second one was found to be more accurate than the first method. This method of slides can be used to derive the relationship between both energy and momentum coefficients versus ε values. The values of α and β averaged 1.237 and 1.10, respectively. The energy and momentum coefficients exhibit higher values in the transition zone than the corresponding ones in the upstream section. This is mainly due to turbulence effect. The values of (α-1/β-1) ranges from 2.71 to 2.81, this range don't exceed 4% for different Reynolds number. The error of (α-1/β-1) for different discharges is less than 5% which could be accepted.
Compound transition , Open channel , Energy loss , Momentum , Turblent.
[1] Al-Khatib, A., Head-discharge relationship in flumes of compound sections. Journal of Irrigation and Drainage Engineering, ASCE, 124 (3), 1998.
[2] Al-Khatib, A., Investigation of momentum and kinetic energy coefficients in asymmetric compound cross-section flumes. Journal of Engineering and Environmental Sciences, 37, 2013.
[3] Ashour, M. A., Aly, T. E., and Mostafa, M. M., Effect of canal width contraction on the hydraulic parameters and scour downstream water structures. Ain Shams Engineering Journal, 10, 203–209, 2019.
[4] Gad, M.H., Zidan, A.R., El-Gamal, M. A., and Abd-Allah, M. G., Compound transitions in open channels. Mansoura University, 2015.
[5] Zidan, A.R., El-Gamal, M. A., Abd-Allah, M. G. and Gad, M.H., Flow characteristics through compound open channels transitions. Journal of Al-Azhar University Engineering Sector, 10 (36), 921-943, 2015.
[6] Henderson, F. M. (1966). “Open channel flow”, McMillan, New York.
[7] Mohanty, P. K., Dash, S. S., Khatua, K. K., and Patra, K. C., Energy and Momentum Coefficients for Wide Compound Channels, WIT Transactions on Ecology and the Environment, 172(11), 87-97,2013.
[8] Musa, R. and Rusaldy, R. A., Analysis of Changes in the Effect Flow Rate on the Open Channel, International Seminar of Science and Applied Technology, 198, 2020.
[9] Seckin, Ardiclioglu, Cagatay, Cobaner,Yurtal Experimental investigation of kinetic energy and momentum correction coefficients in open channels. Academic Journals, 4 (5), 473-478, 2009.
[10] Singh, P., Naik, b., Tang, X., Khatua, K. K., Kumar, A., and Banerjee, S., Models for kinetic energy and momentum correction coefficients for non‑prismatic compound channels using regression and gene expression programming, SN Applied Sciences, 1 , 12-29, 2019.
[11] Tritico, H., and Hotchkiss, R., Unobstructed and obstructed turbulent flow in gravel bed river, Journal of Hydraulic Engineering, 131(8), 635-645, 2005.
[12] Vermaas, D.A. (2009). '' Mixing layers in open channel flow with abrupt bed roughness changes, M.sc. thesis, Wageninges University.
[13] Vishwakarma, B. K., Pradhan, A., and Khatua, K.K. (2017), '' Modelling of Momentum and Energy Correction Coefficients in Meanders'', Hydro-2017 International, L.D. College of Engineering Ahmedabad, India.