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作为河流动力学中的核心问题之一,水流挟沙能力的研究一直受到众多学者的重视.首先以固液两相挟沙水流紊动能量平衡时均方程为理论出发点,在二维、恒定、均匀、充分紊动的流态条件下,经过详细推导了悬移质运动效率系数的表达式,并进一步推导得出水流挟沙能力的结构公式.在此基础上,依据115组天然沙和粉煤灰两种平衡输沙实验的实测数据,结合高含沙水流的流变特性及输沙特性,确定挟沙能力结构公式中的有关参数,获得了具有普遍意义的高含沙水流挟沙能力公式,最后采用大量的黄河、无定河、长江等天然河道实测资料对公式的可靠性进行验证,结果表明计算值与实测值相符合的程度令人满意.该成果对完善河流动力学特别是高含沙水流的理论体系、建立黄河生态输沙需水量模型以及指导治黄工程规划设计等均具有十分重要的现实意义.
As one of the core problems in river dynamics, the research on the sediment carrying ability of water flow has been paid much attention by many scholars.Firstly, based on the time-averaged equation of turbulent energy balance in sediment-laden flow, Uniform and fully turbulent flow conditions, the expression of efficiency coefficient of suspended matter movement is deduced in detail and the structure formula of sediment carrying capacity of water flow is further derived.On the basis of this, based on 115 sets of natural sand and powder Combining with the measured data of two kinds of sediment transport experiments of coal and ash, combined with the rheological characteristics and sediment transport characteristics of high-sediment flow, the relevant parameters in the sediment-carrying capacity formula were determined and the sediment carrying capacity of high-sediment flow with universal significance was obtained Finally, the reliability of the formula is verified by a large number of measured data of natural rivers such as the Yellow River, Wuding River, and Yangtze River.The results show that the calculated value is in good agreement with the measured value.The results are of great value to the improvement of river dynamics, especially It is of great practical significance to establish a theoretical system of high silt water flow, establish a model of ecological sediment demand and water supply and guide planning and design of Yellow River Project.