Three-Dimensional Simulation of Flow Field in Morning Glory Spillway to Determine Flow Regimes (Case Study: Haraz Dam)

Amir Reza Razavi, Hassan Ahmadi

Abstract


Morning-glory spillways are usually used in dams constructed in narrow valleys or those on steeply sloped supports. Furthermore, one can adopt this type of spillway in cases where guiding and diversion tunnels of adequate diameter are available. One of positive characteristics of these spillways is that, their maximum capacity can be approached at relatively low head. This characteristic can be seen as an advantage in cases wherein maximum outflow from the spillway shall be limited. On the other hand, should water head on top of the spillway exceeds the project baseline head, changes in output discharge will be negligible. Morning-glory spillways are commonly used in large dam construction projects across Iran (e.g. Sefid-Rood Dam, Alborz Dam, Haraz Dam, etc.). Given that spillway is one of the most important axillary structures for dams, accurate and realistic characterization of the hydraulic conditions affecting them seems to be necessary. On this basis, the present research is aimed at accurate determination of flow behavior and discharge coefficient of morning-glory spillways from the flow inlet down to horizontal tunnel of the morning-glory spillway of Haraz Dam. For this purpose, the most significant hydraulic parameters (including flow depth, flow velocity, flow pressure at different sections of the spillway, and rate of outflow at spillway) will be determined. In this study, an effort was made to use the numerical model of Flow3D to numerically model three-dimensional flow based on physical model and actual data from one of the largest and most important morning-glory spillways for calibration and verification purposes, and determine accuracy of the numerical modeling and associated error with simulating the numerical model. Results of this study show that, the flow at morning-glory spillways is controlled in either of three modes: flow control at crest, orifice control, and pipe control.


Keywords


Morning-Glory Spillway; Numerical Modeling; Flow3D; Flow Hydraulics.

References


Ervine, D. A., and A. A. Ahmed. "A Scaling relationship for a two-dimensional vertical dropshaft." In Proc. Intl. Conf. on Hydraulic Modelling of Civil Engineering Structures, pp. 195-214. 1982.

Zhao, Can-Hua, David Z. Zhu, Shuang-Ke Sun, and Zhi-Ping Liu. “Experimental Study of Flow in a Vortex Drop Shaft.” Journal of Hydraulic Engineering 132, no. 1 (January 2006): 61–68. doi:10.1061/(asce)0733-9429(2006)132:1(61).

Nohani, E and H. mousavi, 2010. The Effect of number and thickness Vortex Breakers on Discharge Coefficient for the Shaft Spillways. Proceedings of 1th National Conference of water, soil, plant and agricultural mechanization, Islamic Azad University.

FENG H, CHENG G, LIANG J, GAO F. Inspiration of Rainwater Utilization Plan in Denmark for the Construction of Sponge City in China. DEStech Transactions on Environment, Energy and Earth Science [Internet]. DEStech Publications; 2017 Jul 6;(icepe). Available from: http://dx.doi.org/10.12783/dteees/icepe2017/11827

Nohani, Ebrahim. “Numerical Simulation of the Flow Pattern on Morning Glory Spillways.” International Journal of Life Sciences 9, no. 4 (June 5, 2015). doi:10.3126/ijls.v9i4.12671.

Savic, Ljubodrag, Radomir Kapor, Vladan Kuzmanovic, and Bojan Milovanovic. “Shaft Spillway with Deflector Downstream of Vertical Bend.” Proceedings of the Institution of Civil Engineers - Water Management 167, no. 5 (May 2014): 269–278. doi:10.1680/wama.12.00111.

Petaccia, G., and A. Fenocchi. “Experimental Assessment of the Stage–discharge Relationship of the Heyn Siphons of Bric Zerbino Dam.” Flow Measurement and Instrumentation 41 (March 2015): 36–40. doi:10.1016/j.flowmeasinst.2014.10.012.

Houichi L, Ibrahim G, Achour B. Experiments for the discharge capacity of the siphon spillway having the Creager Ofitserov profile. Int J Fluid Mech Res 2006; 33(5):395–406. http://dx.doi.org/10.1615/InterJFluidMechRes.v33.i5.10.

Houichi L, Ibrahim G, Achour B. Experimental comparative study of siphon spillway and overflow spillway. Cour Savoir 2009; 9:95–100.

Gramatky G. Siphon spillway [Dissertation]. University of California; 1928 .

Narany, Tahoora, Mohammad Ramli, Ahmad Aris, Wan Sulaiman, and Kazem Fakharian. “Spatial Assessment of Groundwater Quality Monitoring Wells Using Indicator Kriging and Risk Mapping, Amol-Babol Plain, Iran.” Water 6, no. 1 (December 31, 2013): 68–85. doi:10.3390/w6010068.

Zhang, Xianqi. “Hydraulic Characteristics Of Rotational Flow Shaft Spillway For High Dams.” International Journal of Heat and Technology 33, no. 1 (March 30, 2015): 167–174. doi:10.18280/ijht.330123.

Altomare, C., J.M. Domínguez, A.J.C. Crespo, J. González-Cao, T. Suzuki, M. Gómez-Gesteira, and P. Troch. “Long-Crested Wave Generation and Absorption for SPH-Based DualSPHysics Model.” Coastal Engineering 127 (September 2017): 37–54. doi:10.1016/j.coastaleng.2017.06.004.


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DOI: 10.28991/cej-030943

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Copyright (c) 2017 Amir Reza Razavi, Hassan Ahmadi

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