Velocity and turbulence characteristics around a silt screen

Abstract

Silt screens have been deployed extensively in lakes, rivers and oceans as a physical sediment control device to contain dispersion of silt and clay arisen from dredging activities. By changing the hydraulics of the flow in the vicinity of the project area, the presence of silt screens would affect the distribution of suspended sediment. This paper discusses the velocity profiles and turbulence – key hydraulic determinants to sediment transport – in the presence of a silt screen deployed in closed configuration. The magnitudes of the velocity and turbulence were obtained from the laboratory experiments using the technique of particle image velocimetry. The results also demonstrate that screen penetration depth is a controlling parameter of the flow characteristics. Such findings highlight that silt screen depth is a crucial design parameter in the design and deployment of silt screens.