长江口天然水流中细颗粒泥沙的絮凝作用

FLOCCULATION OF FINE SEDIMENT IN NATURAL WATERS FLOW OF CHANGJIANG ESTUARY

本文根据1978年水文测验资料,分析了长江口水流对细颗粒泥沙絮凝的影响。从中得出:(1)絮凝使长江口泥沙的竖向运动规律发生改变,出现竖向分层流。(2)存在一絮 凝临界流速,只有当流速小于该值时,絮凝泥沙的竖向运动规律才得以体现。(3)在小于絮凝临界流速的水流中,垂线不同高程处的絮凝条件受水流切应力制约。

Based on the data from 1978 year's hydrological survey in Changjiang Estuary, the fine sedimenatary flocculation, which was affected by water flow, was analyzed in this paper. (1) the law of sedimentary velocity motion was changed by flocculation, and formed a vertical stratified flow. (2) there is a critical velocity of flocculation in the natural water flow. The law of vertical motion in sediment particles flooculaed was reflected, only current velocity is less than this velocity. (3) in the water flow where current velocity is less than critical velocity in flocculating condition at different height in vertical direction was restricted by shear stress in water flow.