Numerical Study of Flow Pattern over Free Ogee Spillway (Case Study: Nimrod Reservoir Dam)

Document Type : Research Paper

Authors

1 استادیار، گروه علوم و مهندسی آب، واحد شوشتر، دانشگاه آزاد اسلامی، شوشتر، ایران.

2 دانش آموخته دکتری سازه‌های آبی ، سازمان آب و برق خوزستان.

Abstract

Abstract
Spillways are structures used for releasing the surplus floodwater in necessary conditions from storage dams. Ogee spillway is one of the most common and simplest structures. . In this research, a three dimensional flow field over the spillway was simulated with Flow-3D, using two turbulence models, namely RNG and . First, for precise prediction of hydraulic specifications of over spillway flow, the mentioned turbulence models were validated using data gathered from a laboratory flume (Sivakumaran et al., 1983). Data collected from software validation showed that the RNG turbulence model produced better results than . In the next stage, this model was used for simulating the physical prototype of the Nimrod Reservoir Dam. The measurement factors included pressure and water surface profile. The obtained values were compared to the existing laboratory measurements. Results from the simulation were well consistent with experimental measurements.
Keywords: Flow Pattern, Nimrod Reservoir Dam, Spillway, Flow-3D, Turbulence Model.

Keywords


منابع
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