一个潮流不对称计算方法及其在北仑河口的应用

河口近岸海域潮流不对称对于物质输运、地形地貌变化有重要作用,因此研究河口近岸海域潮流不对称具有重要的意义。从统计学角度出发推导了一种潮流不对称的计算方法,并将该方法应用于全日潮类型的北仑河口。研究认为:从三阶原点矩出发推导的计算方法能够合理的量化潮流不对称;潮流不对称的方向由分潮的相对相位决定,不同分潮对潮流不对称的影响大小由其相对振幅和相对相位共同决定;在正规全日潮海区,三阶原点矩即可满足对潮流不对称的计算。北仑河口潮流表现为落潮流速占主导,潮流不对称空间上表现为口门强于外海,浅滩强于深槽。

A method of quantifying tidal current asymmetry and its application in the Beilun River estuary

It is of very vital significance to sutdy tidal current asymmetry in estuaries and coastal zones, because it plays an important role in material transportation and topographical evolution. A method of quantifying tidal current asymmetry based on statistics is deduced and applied in the diurnal Beilun River estuary. It shows that the method derived from third-order origin moment can reasonably estimate the tidal current asymmetry. The direction of tidal current asymmetry is up to the relative phase of those tidal constituents. The effect of different tidal constituents on tidal current asymmetry depends upon the co action of its relative phase and relative amplitude. For diurnal zone, 3rd order moment can be used to quantify tidal current asymmetry and higher order moments are unnecessary. In the Beilun River estuary, the tidal current is ebb dominant, and the current asymmetry in the river mouth or shallow water is more significant than that of deep channel or outer area.