水库非均匀沙恢复饱和系数特性  

Characteristics of nonuniform sediment recovery saturation coefficient of reservoir

作　　者：李侃禹 LI Kanyu(Center of the Changjiang Waterway Regulation,Wuhan 430070,China)

机构地区：[1]长江航道整治中心

出　　处：《武汉大学学报（工学版）》2018年第9期778-781,816,共5页Engineering Journal of Wuhan University

摘　　要：非均匀沙恢复饱和系数是泥沙数学模型计算的重要参数,其取值合理与否将直接影响到数学模型计算成果的可靠性.目前针对泥沙恢复饱和系数已开展大量理论研究,但对其取值与变化规律尚缺乏一致结论.依据三峡水库库区实测水沙资料,通过分析超饱和输沙状态下库区泥沙含沙量的下包线得到了近似分组挟沙力,基于一维恒定流不平衡输沙方程推求了水库非均匀沙恢复饱和系数,分析了其随重力作用、水动力条件的变化特性,并建立了超饱和输沙条件下水库非均匀沙恢复饱和系数计算公式.研究结果表明,水库非均匀沙恢复饱和系数受重力作用与水流紊动作用共同影响,取值范围可达0.01~10,随粒径的增大而减小,并且与悬浮指标具有良好的负相关关系.The nonuniform sediment recovery saturation coefficient is a very important coefficient in mathematical models,and its value has direct influence on the reliability of model calculations.Great many theoretical studies of recovery saturation coefficient have been carried out;but unanimous conclusions have not been achieved about the value and variation law.Based on the field data of Three Gorges Reservoir,an approximate grouped sediment carrying capacity is obtained by analyzing the lower envelope of sediment concentration in supersaturated sediment transport condition,and the nonuniform sediment recovery saturation coefficient is obtained by solving 1 Dsteady flow and non-equilibrium sediment transport equations.Additionally,the variation characteristics of recovery saturation coefficient with gravity action and hydrodynamic condition are analyzed;and its calculation formula in supersaturated sediment transport condition is obtained.The results indicate that,coefficient of saturation recovery is influenced by gravity and flow turbulence;and its value ranges from 10^-2 to 10^1 increasing with the decrease of sediment particle size;in addition,it has significant negative correlation with suspension index.

关 键 词：恢复饱和系数 非均匀沙 超饱和输沙 三峡水库 

分 类 号：TV14[水利工程—水力学及河流动力学]