潮汐环境下细颗粒泥沙沉降速度研究述评I--基本概念与研究方法

Settling velocity of fine sediment in a tidal environment 1:Definition & study methods

在河口海岸研究领域,泥沙沉降速度是泥沙研究基础理论体系中一个最基本、最核心的物理量,它是直接表征泥沙动力学特征和影响河床底部淤积通量最重要的控制参数之一。综述分为3篇,第1部分主要从沉降定义入手分析,厘清基本概念,总结分析了细颗粒泥沙沉降速度研究方法。到目前为止,细颗粒泥沙沉降过程的环境敏感性特征已经得到普遍的认可,脱离一定的沉降环境,纯粹而笼统地认为向下运动的速度是对细颗粒泥沙沉降速度的曲解。在理论计算、室内试验和现场测量3类研究手段中,建议采用室内试验方法,但测控设备需进一步改进。

Settling （falling） velocity, which is a sensitive and fundamental parameter for each sedimentary researcher, determines the vertical dynamics of sediment and the near-bed deposition flux directly, and its accurate determination has been regarded as a top priority in improving numerical models and understanding of fine sediment transport. During the past studies, hundreds of empirical or semi-empirical formulae are proposed by different laboratory experiments, in-situ observations or theoretical analysis. Even though, it＇s also very hard for the engineers to choose a suitable and self-confident varied or definite value of fine sediment velocity. Based on extensive domestic and abroad hterature study, we present a review on the topic of methods, factors and empirical formulae of the fine sediment settling velocity.