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一、前言在明渠紊流的研究中,阻力特性是个基本问题。明渠水流阻力可分为定床阻力和动床阻力,它们又可分为平面水流阻力(二维)和空间水流阻力(三维)。就定床阻力而言,根据边壁粗糙和水流情况的差异,又可分为光滑,过渡和粗糙区阻力,其中边壁粗糙既可以是均匀的,也可以是非均匀的,可以是二维的,也可以是三维的,因此粗糙壁面的水流阻力特性远比光滑区水流阻力特性复杂。在边壁相同的情况下,明渠水流与管道水流阻力相比,它不仅
I. Preface In the study of open channel turbulence, the resistance characteristic is a basic problem. Open channel flow resistance can be divided into fixed bed resistance and dynamic bed resistance, they can be divided into the plane flow resistance (two-dimensional) and space flow resistance (three-dimensional). In terms of bed resistance, according to the difference between the rough edge of the wall and the flow of water, it can be divided into smooth, transitional and rough area resistance, in which the roughness of the side wall can be uniform or non-uniform, and can be two-dimensional , Or it can be three-dimensional, so the water flow resistance of the rough wall is far more complex than the flow resistance of the smooth area. In the case of the same wall, open channel flow and pipe flow resistance compared to it not only