提出了分析调水工程渠道沿程糙率的系统辨识新方法。依据水力学原理，建立了渠道沿程糙率与粗糙高度ks和水力半径R的函数关系，然后通过数学变换提出了适合最小二乘法进行系统辨识的线性模型。并以南水北调中线工程原型观测资料为基础，考虑渠道断面形状、底坡、渠长变化的影响，应用系统辨识的方法消除水力测量随机误差的干扰,得到了通用的渠道沿程糙率计算公式。

This paper presents a new method for the system identification of channel roughness for the water diversion projects. According to the principle of hydraulics, established the relationship among channel roughness, rough height ks and hydraulic radius R, and deduce the linear model by means of the mathematical transformation to make use of the least square method for the identification. Finally, based on the prototype observation data from the south to north water diversion project and considering the influence of channel section shapes, bottom slopes and lengths etc, a universal formula is obtained for calculation of channel roughness by the system identification.