冲积河流沙质河床推移质级配分布规律  

Bed load graduation of sandy bed in alluvial river

作　　者：张罗号[1] 张红武[2] 赵晨苏 

机构地区：[1]河海大学水利水电学院,江苏南京210098 [2]清华大学水沙科学与水利水电工程国家重点实验室,北京100084 [3]北京科技大学土木与资源工程学院,北京100083

出　　处：《水利学报》2017年第12期1465-1472,共8页Journal of Hydraulic Engineering

基　　金：国家重点研发计划项目(2016YFC0402500)

摘　　要：推移质级配是进行推移质输沙率、河床冲淤等计算模拟的重要条件。本文从分析沙质河床近壁紊动源区内泥沙运动临界图景入手,运用瞬时动量对撞平衡原理得到推移质泥沙临界运动条件,并基于垂向瞬时紊动速度所具有的高斯分布规律,求解随机方程,建立了理论性较强的沙质河床推移质颗粒级配计算公式。黄河与长江的实测资料检验结果表明,本文提出的公式能同天然沙质河床推移质实测资料符合,因而对于确定冲积河流沙质河床推移质泥沙级配具有重要的理论意义和实用价值。Bed load graduation of sandy bed in alluvial river is a key in the calculations such as bed load transport rate, riverbed erosion and siltation. In this paper, pattern of critical condition of sediment trans- port in near-wall region of sandy bed was analyzed firstly, and according to the law of momentum bal- ance, the critical settling-rising condition of bed material in sandy bed was obtained. Based on the vertical instantaneous turbulent velocity abiding by Gaussian distribution, a theoretical relation for calculating bed load graduation in sandy bed was addressed by solving the stochastic equation. The formulae were verified by measured data from the Yellow and Yangtze Rivers, and the results showed that the measured data agreed well with proposed formulae. This study has theoretical significance and practical value for determining bed load graduation of sandy bed in alluvial river.

关 键 词：泥沙级配 推移质 紊流 动量 沙质河床 

分 类 号：TV143[水利工程—水力学及河流动力学]