Sulaimani Journal for Engineering Sciences (SJES)

Experimental Investigation of the Influence of Step Height on Energy Dissipation and Flow Characteristics in Stepped Spillways

1, a Wazira Qadir 2, a Ahang S. Ali 3, a Kawa Z. Abdulrahman

a University of Sulaimani, College of Engineering, Department of Water Resources Engineering

Abstract

Stepped spillways have become increasingly popular due to their stability and ability to dissipate energy effectively. While previous studies have evaluated various aspects of stepped spillways, this paper specifically investigates the impact of step height on energy dissipation and flow characteristics. The study aims to analyze the flow and energy dissipation rates of stepped spillways with different step heights, providing valuable insights into the design and construction of such structures. To achieve this, a series of laboratory experiments were conducted using stepped spillway models of varying step heights. The models were subjected to various flow rates within a horizontal flume of 0.3 m width, with a non-dimensional discharge (yc/h) range of 0.14 to 3.5. The outcomes indicated that the model with a larger step height exhibited greater energy dissipation, up to approximately 28%, compared to the model with a smaller step height.

Keywords:

Flat stepped spillway, Energy dissipation, step height, Flow regime

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