根据实测资料 , 采用3点法、5 点法对比计算分析了原型和长江防洪实体模型的垂线平均流速两者间差异，同时比较分析原型与模型流速沿水深分布偏离程度。采用明渠对数流速公式探讨了模型变态后流速沿垂线分布的规律，在此基础上提出了长江防洪实体模型垂线平均流速与相对水深某位置处点流速的关系，观测资料分析表明，模型相对水深为 0.6 处的点水深处流速与垂线平均流速基本一致。

According to the comparative analysis of the differences between data measured by three-point method and five-point method used in the Yangtze River Flood Control prototype and model, and those data measured by verticall-average flow velocity method adopted in the physical model, the deviation degrees of prototype-model flow velocities along water depth are compared. The authors discuss the law of velocity distribution along the vertical direction after model metamorphosis using the Nullah-Logarithmic velocity equation, and, on the basis of this analysis, propose the relations between the average vertical velocity and the relative location of the depth. Observation data analysis show that velocity of the 0.6 relative water depth is basically consistent with the average vertical velocity.