摘要
基于ECOMSED模型研究分析单纯潮流作用下黄河入海泥沙在渤海中的输运特征。研究表明,渤海海域陆架坡度远小于内波特征参量,因此除黄河入海口附近以及其他近岸极浅海域之外,单纯潮流作用下渤海大部分海域的表层悬沙含量较低,但与实际水动力条件的空间分布格局基本一致。悬沙含量垂向分布特征明显,底边界层内因为较大的垂向湍流粘性系数,因此悬沙含量可以维持较高的水平,而底边界层之外悬沙含量迅速降低2～3个数量级;同时悬沙含量呈现出比较明显的潮周期(M2)变化特征。潮流作用下,绝大部分黄河入海泥沙沉积在黄河三角洲附近,只有少量悬沙可以发生长距离输送。黄河入海泥沙输运通量在口门外呈现一对涡状结构,成为水下三角洲南北两侧泥质沉积区形成的主要机制。
On the basis of ECOMSED,a state-of-the-art model considering 3D baroclinic circulation and sediment transportation,the contribution due to the tidal currents to the transportation of the sediment from the Yellow River in the Bohai Sea is investigated.Calculations found that the continental slope of the Bohai Sea is far less than that of the internal wave characteristics.Although it was almost the same spatial distribution structure with those under the actual hydrodynamical environment,the surface sediment concentration was low just under the condition of tidal currents,except in the Yellow River Estuary and waters very close to the coastline,where the suspended sediment concentration oscillated with the frequency of M2 tidal constituent.The vertical distribution indicated that the sediment concentration was high in the bottom boundary layer（BBL）,where the vertical viscosity coefficient was much larger than that out of the BBL and the sediment concentration out of the BBL was correspondingly lower by a factor of 10-2 ～ 10-3.Most of the sediment deposited around the Yellow River delta and only a little was transported far away.The pattern of sediment transportation structure showed a pair of eddies out of the Yellow River estuary,which contributed mostly to the formation of two muddy areas of the Yellow River submerged-delta.
出处
《泥沙研究》
CSCD
北大核心
2011年第1期51-59,共9页
Journal of Sediment Research
基金
自然科学基金项目(40506024、40771030、41076003)
关键词
黄河入海泥沙
渤海
潮流
数值模拟
suspended sediment
Yellow River
Bohai Sea
tidal current
numerical simulation
