Numerical and Experimental Investigation of the Distribution of Non-Cohesive Sediments in the Body of Rock-Fill Dams

Document Type : Research Article

Authors

1 Ph.D. Student, Department of Water Engineering, Faculty of Agriculture, Bu-Ali Sina University, Hamadan, Iran

2 Assistant Professor, Department of Water Engineering, Faculty of Agriculture, Bu-Ali Sina University, Hamadan, Iran

3 Assistant Professor, Department of Civil Engineering, Bu-Ali Sina University, Hamadan, Iran

4 Associate Professor, Department of Water Engineering, Sari Agricultural Sciences and Natural Resources University, Sari, Iran

Abstract

Use of non-core rock-fill dams is one of the structural methods for flood control. Flood flows are usually known to have high sediment loads, and carry high content of sediment into the body of rock-fill dam with large pores that characterize the body of these types of dams. It is thus essential that the sediment concentration be determined at different points of the body so that one could determine the critical points of sedimentation, the amount of sediment passing and the amount of sediment trapped. Therefore, in the present study, a mathematical model of flow simulator was implemented in MATLAB, on the basis of Saint-Venant equations and Forchheimer equation, using finite volume method. Then the mathematical simulator model of the distribution of non-cohesive sediment concentration in the body of dam was developed, based on the model output and sediment transport equation, using F.V.M. The model determines the value of the sediment concentrations at different points of the body on the basis of the gridding from the previous stage. The experimental results were used to evaluate the output of these models. The comparison of the experimental and numerical results seemed to verify the accuracy of the numerical model. The mean value of the relative error of sediments was calculated to be 8.14 percent as determined by the comparison made between the measured data on sediment distribution and the values calculated in three sections of the body of dam.

Keywords


حیدری، م. (1386). "مدل دوبعدی جریان عبوری از داخل و روی سدهای پاره­سنگی و کاربرد آن در کنترل سیلاب"، رساله دکتری تأسیسات آبیاری، دانشکده کشاورزی، دانشگاه تربیت مدرس، تهران.
سامانی، ج. م. و. و عمادی، ع. (1382). "تعیین رابطۀ گرادیان هیدرولیکی بحرانی انتقال رسوبات غیرچسبنده در سدهای تأخیری پار ه­سنگی"، مجموعه مقالات چهارمین کنفرانس هیدرولیک ایران، شیراز.
قادری، ک.، سامانی، ج. م. و. و عمادی، ع. (۱۳۸۴). "بررسی روابط مختلف تراوش غیردارسی و مدل ریاضی محاسبه جریان در محیط‌های متخلخل مستغرق"، پنجمین کنفرانس هیدرولیک ایران، کرمان.
قدیمی، پ. (1392). دینامیک سیالات محاسباتی کاربردی، مبتنی بر روش­های تفاضل محدود، اجزاء محدود و حجم محدود (جلد دوم). انتشارات دانشگاه صنعتی امیرکبیر، تهران.
محمودیان شوشتری، م. (1389). هیدرولیک آبهای زیرزمینی، انتشارات دانشگاه شهید چمران، اهواز.
Addiscott, T.M. and Whitmore, A.P. (1987). "Computer simulation of changes in soil mineral nitrogen and crop Nitrogen during autumn, winter and spring", Journal of Agricultural Science, 109:141–157.
Aldrighetti, E. (2007). "Computational hydraulic techniques for the Saint Venant equations in arbitrarily shaped geometry", PhD thesis, Universita degli Studi di Trento. Trento, Italy. 
Chapokpour, J. and Amiri-Tokaldany, E. (2013). "Introducing a relationship for estimation of the sediment transport rate through rockfill structures", Journal of Water Sciences Research, 5(2):35-42.
Cheng, N.S, (1997). "Simplified settling velocity formula for sediment particle. Journal of Hydraulic Engineering", ASCE, 123(2):149–152.
Faghihirad, Sh., Lin, B. and Falconer, R. A. (2015). "Application of a 3D layer integrated numerical model of flow and sediment transport processes to a reservoir", Water, 7(10):5239-5257.
Joy, D. M., Lennox, W. C. and Kouwen, N. (1991). "Particulate transport in porous media under non-linear flow condition", Journal of Hydraulic Research, 29(3):373-385.
Kempe, T., Vowinckel, B., and Fröhlich, j. (2014). "On the relevance of collision modeling for
interface-resolving simulations of sediment transport in open channel flow
", International Journal of Multiphase Flow, 58:214-235.
Mousavi, S.A., Amiri-Tokaldany, E. and Davoudi, M. H. (2011). "A relationship to determine the critical hydraulic gradient and noncohesive sediment transport discharge in rockfill dams", Research Journal of Environmental Sciences, 5(5):399-413.
Nazemi, A. (2011). "Flow hydraulics and sediment transport in pervious rockfill detention dams", PhD thesis. University of Putra. Malaysia.
Rubey, W. (1933). "Settling velocities of gravel, sand and silt particles", American Journal of Science, 225:325–338.
Sakthivadivel, R. (1972), "Sediment transport through a porous column". In Shen, H W, Ed, Sedimentation.
Samani, H. M. V., Samani, J. M. V. and Shayannejad, M. (2003). "Reservoir routing using steady and unsteady flow through rockfill dams", Journal of Hydraulic Engineering, 129(6):448-454.
Scheidegaer, A. E. (1961). "General theory of dispersion in porous media", Journal of Geophysical Research, 66(10): 3273-3278.
Streeter, V. L., Wylie E. B. and Bedford, K. W. (1998). "Fluid Mechanics", 9th ed., McGraw Hill Book Company, New York, pp.740.
Van Rijn, L. C. (1984). "Sediment transport, part II: suspended load transport", Journal of Hydraulic Engineering, ASCE, 110(11):1613–1641.
Van Rijn, L. C. (1987). "Mathematical modelling of morphological processes in the case of suspended sediment transport", Delft Hydraulics Communication, No. 382, The Netherlands.
Versteeg, H. and Malalasekera, W. (2007). An introduction to computational fluid dynamics: the finite volume method, 2nd Edition. Pearson Education Ltd, Harlow, England.
Wu, W. (2007). Computational river dynamics. Taylor & Francis Group, London, UK.
Wu, W. and Wang, S. S. Y. (2006). "Formulas for sediment porosity and settling velocity", Journal of Hydraulic Engineering, ASCE, 132(8):858–862.