【摘要】 根据长江和黄河实测的流速、悬移质含沙量及其级配的垂线分布资料，分析了它们变化的规律性，检查了现有理论和经验公式与实测资料的符合程度，并对有关参数进行了探讨．分析表明：各垂线流速分布可以用指数流速分布公式和对数流速分布公式表示，各垂线含沙量分布既可用指数分布又可用对数流速分布导出的含沙量公式表示．相对水深η＝ｙ／ｈ＝０．４处的流速和含沙量及级配基本上都等于垂线平均值，从而可知，用η＝０．４处的流速和含沙量算得的单宽输沙率与用垂线平均流速和含沙量所求得的单宽输沙率是相等的．卡门常数Ｋ值和满宁系数η值都随含沙量的增加而减小．更多还原

【Abstract】 In this paper, the vertical distributions of velocity sediment concentration and particle gradation according to the measured data of the Yangtze River and Yellow River are analyzed, the degree of conformity for the existing theories and empirical formulas to the measured data is verified and the problem about several parameters is discussed. It is found that the velocity profile may be described by exponential law or logarthmic law and the sediment concentration profile can be derived from exponential velocity distribution or from logarithmic velocity distribution accordingly. It is also found that magnitudes of velocity, cncentration and gradation at the location of the relative depth η=y/h=0.4 are the same as the depth -average one. Analysis also shows that the Karman constant K and the Manning coefficient n decrease with the increase of sediment concentration.更多还原