Hydrodynamics and suspended sediment concentration of tide-induced bottom boundary layer have been observed by a self-designed measuring system during August 8-10, 2013 at intertidal flats in the central part of Jiangsu coast. An advanced Acoustic Doppler Velocity Profiler "Vectrino Profiler" with a 1mm vertical resolution, was used to acquire a velocity profile within the depth of 3-6cm above the surface of tidal flats. ADCP was positioned upwards to obtain velocities between 35cm above the bed and the water surface with a minimum resolution of 10cm. Karman-Prandtl model was adopted to reconstruct BBL velocity profiles and estimate BBL parameters. It indicates that the vertical structure of velocity profiles maintains logarithmic distribution near the bottom in most time of a tidal period except the slack. Meanwhile, the friction characteristics of BBL are also discussed. Velocities close to the bottom brings preciser estimation of shear stress and roughness length. A roughness length with less fluctuation is instructional in numerical modeling.
Near-bed Velocity Profile and Friction Characteristic of Tide-induced Bottom Boundary Layers on the Mudflats of Jiangsu Coast, China
Zhang, Qian, Gong, Zheng, Zhang, Changkuan, Jin, Chuang, and Huan Li. "Near-bed Velocity Profile and Friction Characteristic of Tide-induced Bottom Boundary Layers on the Mudflats of Jiangsu Coast, China." Paper presented at the The Eleventh ISOPE Pacific/Asia Offshore Mechanics Symposium, Shanghai, China, October 2014.
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