Abstract
A rectangular broad crested weir is the one mostly used in hydraulic structures for measuring flow rates in open channels and rivers. This study is focused on finding the suitable position of the depth above the weir as control section for estimating the flow rate while avoiding the troubles of approach velocity. It was predicted that the end edge of the weir, as a control section, relates to the critical depth (Yc) as a function of the end depth (Ye). To determine the relationship between these, experimental tests were achieved with ten different values of the longitudinal slope. Statistical regression analysis indicated the relationship between Yc and Ye as about 1.522. Consequently, a new flow rate formula was derived to estimate the flow over the weir and provided a good agreement with the experimental tests. A 3D ANSYS FLUENT Ver. V.16.1 CFD model was also applied to simulate the problem and verify the equation. The water volume fraction and the stream flow pattern were taken into the consideration. The model was able to simulate the problem with a good accuracy for all cases with a percentage error less than 10% when compared to experimental results. Thus indicating that CFD models could be relied upon for describing complex flows.
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References
Amir HA, Rajaratnam N, David ZZ (2013) Discharge characteristics of weirs of finite crest length with upstream and downstream ramps. J Irrig Drain Eng 139:75–83
Ehsan G, Javad F, Naser S (2012) Flow characteristics of rectangular broad-crested weirs with sloped upstream face. J Hydrol Hydromech 60:87–100
Farzin S, Sanaz P, Ali HD, Davood FZ (2011) Discharge relations for rectangular broad-crested weirs. Tarim Bilim Derg J Agric Sci 17:324–336
Maghsoodi R, Mohammad SR, Hamed S, Hazi MA (2012) 3D-simulation of flow over submerged weirs. Int J Model Simul 32(4)
Hooman Hoseini S, Habib Musavi J, Sadegh Rafi V (2013) Determination of discharge coefficient of rectangular broad-crested side weir in trapezoidal channel by CFD. Int J Hydraul Eng 2(4):64–70
Samadi A, Arvanaghi H (2014) CFD simulation of flow over contracted compound arched rectangular sharp crested weirs. Int J Optim Civ Eng 4(4):549–560
Shaker AJ, Safa SI, Rondk AJ (2014) Surface roughness effects on discharge coefficient of broad crested weir. Res J Appl Sci Eng Technol 7(24):5227–5233
Seyed HH, Hossein A (2014) Flow over a broad-crested weir in subcritical flow conditions, physical study. J River Eng 2(1)
Sadiq SM (2014) Variation of discharge coefficient of spillway and broad crested weir due to the effective of the longitudinal slope in a non-horizontal channel. J Environ Sci Eng A 3(5):287–295
Ahmed S (2015) The coefficient of broad-crested weir in natural channels. Int J Sci Eng Inven (IJSEI) 1(1):1–13
Al-Hashimi SA, Madhloom H, Khalaf R, Nahi T, Al-Ansari N (2017) Flow over broad crested weirs: comparison of 2D and 3D models. J Civ Eng Archit 11:769–779
Sadiq SM, Al-Sharify ZT (2018) Experimental work and CFD model for flowrate estimating over OGEE spillway under longitudinal slope effect. Int J Civ Eng Technol (IJCIET) 9(13):430–439
Thulfikar RA, Abdul-Sahib TA, Zainab AN (2019) Laboratory experiments and numerical model of local scour around submerged sharp crested weirs. J King Saud Univ Eng Sci. https://doi.org/10.1016/j.jksues.2019.01.001
Chin DA (2006) Water resources engineering, 2nd edn. Prentice Hall
Chow VT (1986) Open-channel hydraulics. McGraw-Hill, New York, pp 365–380
Khurmi RS (2009) A textbook of hydraulic, fluid mechanics and hydraulic machines. Ram Nagar, New Delhi
Rajput RK (2008) A textbook of fluid mechanics and hydraulic machines. Ram Nagar, New Delhi
Sturm TW (2001) Open channel hydraulics. McGraw-Hill, New York
Subramanya K (1998) Flow in open channel. Tata McGraw Hill, New Delhi
Vennard K, Street L (1996) Elementary fluid mechanics. McGraw-Hill
Boiten W (2002) Flow measurement structures. Flow Meas Instrum 13:203–207
Soong TT (2004) Fundamentals of probability and statistics for engineers. Wiley, New York, USA
Aal GMA, Sobeah M, Helal E, El-Fooly M (2017) Improving energy dissipation on stepped spillways using breakers. Ain Shams Eng J. https://doi.org/10.1016/j.asej.2017.01.008
Al-Sharify ZT (2017) Flow and mixing of complex fluids. PhD thesis, University of Birmingham
Al-Sharify ZT, Zhao Y, Barigou M (2014) Comparing the performance of different impellers in mixing viscoplastic fluids: CFD, theory and experiment. In: The 5th Birmingham environment for academic research (BEAR) conference, Birmingham, UK
Ming-Liang Z, Yong-Ming S (2010) A 3D non-linear k–ε turbulent model for prediction of flow and mass transport in channel with vegetation. Appl Math Model 34(4):1021–1031
Mu Z, Zhang Z, Zao T (2012) Numerical simulation of 3-D flow field of spillway based on VOF method. Int Conf Mod Hydraul Eng Procedia Eng 28:808–812
Acknowledgements
The authors would like to thank Mustansiriyah University (www.uomustansiriyah.edu.iq) Baghdad-Iraq for its support in the present work and the Hydraulic Laboratory staff in the College of Engineering for their support and helps with the experiments.
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Muhsun, S.S., Talab Al-Osmy, S.A., Al-Hashimi, S.A.M., Al-Sharify, Z.T. (2020). Theoretical, CFD Simulation and Experimental Study to Predict the Flowrate Across a Square Edge Broad Crested Weir Depending on the End Depth as a Control Section. In: Mohamed Nazri, F. (eds) Proceedings of AICCE'19. AICCE 2019. Lecture Notes in Civil Engineering, vol 53. Springer, Cham. https://doi.org/10.1007/978-3-030-32816-0_2
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