【作者】 刘炳锐； 龚政； 徐贝贝； 张长宽；

【Author】 LIU Bingrui;GONG Zheng;XU Beibei;ZHANG Changkuan;Jiangsu Key Laboratory of Coast Ocean Resources Development and Environment Security,Hohai University;State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering,Hohai University;

【机构】 河海大学江苏省海岸海洋资源开发与环境安全重点实验室； 河海大学水文水资源与水利工程科学国家重点实验室；

【摘要】 辐射沙脊群位于南黄海大陆架,呈辐射状分布于江苏外海。本文基于2015年12月及2016年7月大潮期间在南黄海辐射沙脊群的西洋水道进行定点全潮观测的实测数据,分析了冬、夏两季西洋海域的水沙特性以及底部边界层参数的变化。结果显示,西洋海域存在流速和潮位过程不对称现象,涨潮历时小于落潮历时,涨潮流速明显大于落潮流速,冬季的不对称性更为显著。冬季含沙量明显大于夏季,流速在悬沙输运中占主导,悬沙输运率与流速变化密切相关。冬、夏两季的全潮过程中大部分时刻的垂向流速剖面符合对数分布,利用对数剖面计算边界层参数,摩阻流速和切应力随着流速的增大而增大,由于该海域流速较大,底部切应力大于临界启动切应力,深槽冲刷,夏季底部切应力较大,冲刷更为明显;冬夏两季粗糙长度较为接近,说明西洋海域底部沉积物粒径和微地貌等季节性变化不大。更多还原

【Abstract】 Radial sand ridges spread in a fan-shaped pattern over the seabed of the southern Yellow Sea along the Jiangsu Coast.Based on the measured data of observation during the force tide of December 2015 and July2016 in the Xiyang waterway,this paper analyzed the tidal period of the Xiyang waterway during the winter and summer seasons as well as the parameters of the bottom boundary layer.According to the measured results, there are asymmetries over flow phenomena and tidal level in the tidal processes in the Xiyang waterway, which is more obvious in winter.The sediment concentration in winter was significantly higher than that in summer,the single-width transport rate of suspended sediment was closely related to the velocity process.The vertical velocity profile in most of the winter and summer tide conforms to the logarithmic distribution,therefore, the logarithmic profile is used to calculate the boundary layer parameters.Last but not least,the friction velocity and shear stress in the winter and summer show great relativity to the average velocity.The bottom shear stress is greater than the critical starting shear stress due to high flow rate,because of which,the waterway is eroded.The erosion is more obvious in summer.The rough length during winter and summer is closer,indicating that the difference of sedimentation and microtopography at the bottom of the Ocean are not significant.更多还原