摘要
近岸海域的波浪、潮流及海流等动力因素具有周期性和时间、空间尺度差异大的特点,在综合考虑各动力因子的联合作用时具有较大的难度。本文根据平动动能叠加原理给出了一种近岸动力因子的表达形式,并提出了海洋波动有效速度的概念,结合水沙界面处泥沙通量的切应力与挟沙力关系,得到了水流挟沙力的新的计算公式。指出了水流挟沙力与水流临界速度有关,并且该水流临界速度随水深的增大及相对糙率的减小而增大。采用近岸实测数据和模拟结果,对本文的近岸水流挟沙力公式进行了验证,结果表明该公式的计算值与实测值吻合较好,可以适用于近岸海域。
In nearshore waters, the spatial and temporal scales of waves, tides current and circulation have great difference. It is difficult to combine these factors＇ effects to predict the transport of sediment. This paper proposed a concept of ocean waves significant velocity, which combine the effects of wave, tide and ocean current by the hori- zontal kinetic energy superposition principle. Through comparing the relation between shear stress at the water- sediment interface and sediment carrying capacity, with the condition of equilibrium of sediment flux, a new formula of sediment carrying capacity which connected to the ocean waves significant velocity is derived. The sediment carrying capacity is related to the critical velocity that is increased with the water depth and reduced with the relative roughness. Finally,the field data of 30 observation stations and 590 simulation data have been used to verify this paper＇s formula. The results show that the new formula is good agreement with the field and simulation data. The formula of sediment carrying capacity could be used to simulate the nearshore sediment transport.
出处
《海洋学报》
CAS
CSCD
北大核心
2014年第5期136-141,共6页
基金
国家自然科学基金资助项目(41276017)
国家自然科学基金资助项目(41376120)
国家海洋局海洋公益性行业科研专项经费项目(201205005)
国家海洋局海洋公益性行业科研专项经费项目(201105006)
关键词
水流挟沙力
泥沙通量
水沙界面
近岸海域
海洋波动有效流速
sediment carrying capacity
sediment flux
water-sediment interface
coastal area
ocean waves significant velocity
