A Study of Turbulent Shear Stress on Fine-Grained Suspended Sediment Flocs Size in the Yangtze Estuary

Abstract:

During the two surveys at both spring and neap tides in wet (July-August 2008) season, measurements of flow, turbulence, suspended sediment concentration (SSC), fine-grained sediment particle mean diameter (Dm) were carried out over 26 h that covered two M₂ semidiurnal cycles in the middle north channel of the Yangtze estuary. The preliminary observations data show complex temporal and seasonal variation in estuarine flocculation of fine-grained sediment. In the high-turbidity and high-energy area of the Yangtze estuary, the flocculation processes indicate that the turbulence shear stress maybe the most important factor to the fine-grained sediment flocculation processes during the spring and neap tide cycle change. There exists a turning point of flocs Dm vs. turbulent shear stress. The neap tidal critical turbulent shear stress is around 0.1 Nm^-2, much smaller that the spring tidal data of about 0.5 Nm^-2.

• Periodical: Applied Mechanics and Materials (Volumes 353-356)
• Pages: 2720-2723
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.353-356.2720
• Online since: August 2013
• Authors: Jiang Cheng*, Wei Pan, Pan Jun Du
• Keywords: Fine-Grained Sediment, Flocculation, Turbidity Maximum, Turbulent Shear Stress

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