Particle Image Analysis of Open-channel Flow at a Backward Facing Step Having a Trench

Article type: Research Article

Authors: Fujita, I.

Affiliations: Research Center for Urban Safety and Security, Kobe University, Rokkodai, Nada-ku, Kobe 657-8501, Japan.

Abstract: Characteristics of open-channel flow at a backward facing step with a trench section were experimentally investigated. The experiments were performed using a straight open channel flume by varying the trench length. Two-dimensional velocity measurements by the particle tracking velocimetry (PTV) were conducted at the trench section using a high-resolution video camera of 12 fps. Mean and turbulent flow properties along with the water surface profile were measured for various aspect ratios of the trench. It was also observed that the flow at the trench begins to oscillate periodically for a specific aspect ratio of the trench.

Keywords: PTV, backward facing step, trench, hydraulic jump, hydraulic oscillation

Journal: Journal of Visualization, vol. 5, no. 4, pp. 335-342, 2002