中文摘要：

对数型流速分布公式是描述河渠垂向流速分布的常用方法,但是公式中卡门常数K、积分常数B和尾流强度系数Π的取值一直没有确定。本文研究了对数型流速分布公式中上述3个参数的取值范围及其变化对流速计算结果的影响,以及摩阻流速u_＊不同计算方法的精度和优缺点。对比分析了877个测点的流速计算值和实测值,结果表明：在浅宽和窄深渠道中,K取0.395,B取5.419时,不含尾流修正函数的对数型流速分布公式在计算流速分布上仍然具有较高的精度,可满足实际工程的需要。

英文摘要：

Logarithmic velocity distribution formula is commonly used to calculate vertical velocity, but Kar man constant K, integral constant B and coefficient of wake strength /7 cannot be confirmed at present. The value range of these three parameters and their effects on velocity calculation are studied in this pa per. The precision, advantages and disadvantages of different calculation methods for friction velocity u. is also discussed. Through comparing 877 calculated and experimental velocity data, it is proved that when taking K as 0.395 and B as 5.419, the logarithmic velocity distribution formula without wake strength iscurate enough to satisfy the requirements of actual engineering.