Vertical structures of momentum exchange coefficient and sediment concentration are the keys in the research on es- tuarine and coastal suspended sediment transport. Based on the parabolic mixing length distribution p...Vertical structures of momentum exchange coefficient and sediment concentration are the keys in the research on es- tuarine and coastal suspended sediment transport. Based on the parabolic mixing length distribution pattern, the distribu- tion pattern of vertical momentum exchange coefficient which is suitable for estuarine and coastal waters is constructed. A compari^n with steady flow and measured momentum exchange coefficient during one tidal cycle in the Menai Strait of England shows that the result of this pattern is closer to the measured values than those of commonly used Rouse' s and van Rijn's patterns, and the pattern is also suitable for estuarine and coastal waters. Successively, based on the precon- dition that momentum exchange coefficient is equivalent to sediment turbulent diffusion coefficient, and combining with the Diffusion Theory, we obtain the exponential vertical distribution pattern of sediment concentration, which is also suitable for estuafine and coastal waters, Thereby, using measured vertical stratified sediment concentration data of the South and the North Passages of the Yangtze Estuary and Zhoushan archipelago waters for fitting calculation, and comparing the results with those from Rouse's (1938) and Zhang et al. 's (1989) formulas, the results show that the exponential vertical distribution pattern of sediment concentration obtained in the present study not only overcomes the defect of Rouse's formula that the surface sediment concentration will be 0, but also has a holistic higher precision along the vertical lines than those of Rouse's and Zhang et al. 's formulas.展开更多
基金supported by the National Key Basic Research Development Programof China (973 Program, Grant No.2010CB429002)the Foundation of the Key Laboratory of Port, Waterway and Sedimentation Engineering, Min-istry of Communications, PRC (Subject : The Vertical Characteristics of suspended sediment transport in Estuary)the Natural Science Foundation of Jiangsu Province (Grant No.BK2007179)
文摘Vertical structures of momentum exchange coefficient and sediment concentration are the keys in the research on es- tuarine and coastal suspended sediment transport. Based on the parabolic mixing length distribution pattern, the distribu- tion pattern of vertical momentum exchange coefficient which is suitable for estuarine and coastal waters is constructed. A compari^n with steady flow and measured momentum exchange coefficient during one tidal cycle in the Menai Strait of England shows that the result of this pattern is closer to the measured values than those of commonly used Rouse' s and van Rijn's patterns, and the pattern is also suitable for estuarine and coastal waters. Successively, based on the precon- dition that momentum exchange coefficient is equivalent to sediment turbulent diffusion coefficient, and combining with the Diffusion Theory, we obtain the exponential vertical distribution pattern of sediment concentration, which is also suitable for estuafine and coastal waters, Thereby, using measured vertical stratified sediment concentration data of the South and the North Passages of the Yangtze Estuary and Zhoushan archipelago waters for fitting calculation, and comparing the results with those from Rouse's (1938) and Zhang et al. 's (1989) formulas, the results show that the exponential vertical distribution pattern of sediment concentration obtained in the present study not only overcomes the defect of Rouse's formula that the surface sediment concentration will be 0, but also has a holistic higher precision along the vertical lines than those of Rouse's and Zhang et al. 's formulas.