Numerical and Experimental Study of the Unsteady Flow with Different Distance Steps in Body of Rockfill Dam

Document Type : Original 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, Hamedan, Iran

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

4 Department of Water Engineering, Sari Agricultural Sciences and Natural Resources University,sari,iran

Abstract

Non-Core Rockfill dam is one of the low-cost methods of flood control for single or multiple. Rockfill dams are one type of detention dams and capable to reduce the output peak of flood to the entrance flood. Therefore, studying the flow behavior and flow routing is very important. In this study, Performance of the Saint–Venant equations studied via finite volume method and on the basis of the non-Darcy relations in the simulation of unsteady flow in the body of Rockfill dam, assuming the condition of the unknown output and with two different distance steps (5 and 10 cm). For this purpose, first mathematical model of mentioned equations prepared in MatLab and then in order to evaluate the performance of this model used the results of conducted experiments in the hydraulic laboratory of Agriculture faculty of Bu-Ali Sina University of Hamadan on the Rockfill dams. The results showed the good accuracy of mentioned numerical model in flow simulation. The mean of depth relative error and the mean absolute of velocity relative error are -12.76% and 7.26% on the basis of comparison between measured data and calculated data of flow velocity and depth for Δx=10 cm in three sections and three depth layer of 5, 10 and 15 cm in body of Rockfill dam, and by decreasing the distance step from 10 cm to 5 cm, the accuracy of the model increased in the depth estimation section and the velocity estimation section about 4.5% and 2.1%, Respectively.

Keywords


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