Turbulent Flow over Step with Rounded Edges: Experimental and Numerical Study
Publication: Journal of Hydraulic Engineering
Volume 126, Issue 1
Abstract
The study of turbulent flow over man-made obstacles and natural bed forms is an area of active research. This investigation was conducted to explore the differences between flow over a backward facing step and flow over a step with gradual transitions. Detailed measurements of longitudinal mean velocity and turbulence intensity were obtained using a one component LDV system. A turbulence-based numerical model was implemented to reproduce the measured flow variables and to explore additional flow characteristics, including Reynolds stresses and eddy viscosity. The separation that takes place in the rounded expansion plays a significant role in the flow pattern. In contrast to flow over a backward facing step, flow over a step with rounded edges shows a relatively shorter separation bubble and a slower return to the developed flow condition.
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Information & Authors
Information
Published In
Journal of Hydraulic Engineering
Volume 126 • Issue 1 • January 2000
Pages: 82 - 85
History
Received: Aug 8, 1997
Published online: Jan 1, 2000
Published in print: Jan 2000
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