横比降

横比降在长江口河演中的作用

Role of Transverse Slope in River-Bed Evolution in the Changjiang Estuary

弯道水流的动力特性主要集中在水面横比降、横向环流、流速重分布等方面。

Bend flow momentum characteristics is mainly concentrated in the surface sloop , cross circulation and the velocity re-distribution .

河口段下游弯道的水面横比降大于上游弯道，当地水动力强度和弯道曲率是其主要影响因素。

The local hydrodynamic intensity and the bend curvature are main factors that make the transversal slope of water surface in the lower bend larger than that in the upper bend .

本文在前人的弯道研究基础上对变换后的基本方程式作了修正，修正后的方程式可以考虑弯道水面横比降所引起的环流对垂线平均流速的影响。

In this paper a modification of basic equations is presented , the influence of secondary flow at river bend on vertical distribution of velocity can be taken into consideration in the modified equations .

通过分析有如下认识：1、北港上口通道的兴衰变迁与南北港水流阻力的变化造成的水面横比降变动及沉积物疏松易冲的边界条件有关。

There are several cognitions after analyzing : 1 . The change of the upper channel of the North Channel is correlated to change of the transverse slope caused by change of the flow resistance and the loose boundary conditions .

本文着重对弯道水流水面横比降、横向环流、纵向垂线平均流速分布规律及弯道输沙特性研究进展进行了阐述分析，以便为生产科研方面服务。

This paper discusses the research development of such laws as the lateral slope of the water surface , secondary circulation flow , average velocity along vertical line , distribution of the main streamline and sediment transport characteristics in the river bend .

突出体现在水流失去平衡，产生凹岸高、凸岸低的横比降，而且弯道急流表面还将产生水冠较大的菱形冲击波。

These mainly behave at that the water flow losses it 's instability and generates the transverse gradient that the water surface of concave bank is higher than convex bank , and that the big diamond impact wave even occurs on the water surface .

利用黄河1956~2004年实测资料，论证了表征健康黄河标志的低限流量、河道最大排洪能力、平滩流量、滩地横比降、水质类别、湿地规模、水生生物、供水能力等指示因子的阈值范围。

The hydrologic data from 1956 to 2004 are used to analyze the threshold of the relevant indexes including the minimum flow , maximum flood discharging capacity , bank-full discharge , water quality , wetland area , aquatic life and capacity of water supply .