Shape Effects on Resistance to Flow in Smooth Rectangular Channels

摘要

The effectiveness and generality of Kazemipour's method for dealing with the effects of cross sectional shape on flow resistance in open channels was investigated for the case of smooth rectangular channels. The chamber used for the experiment and procedures for establishing uniform flow and normal depth are described. Kazemipour's method shifts the experimental resistance data for flow in smooth channels onto the universal diagrams for smooth circular pipes. The shape factor establishes a simple correlation between tha flow in circular pipes and open channels and permits the friction factor and the average velocity of the flow in the channel to be calculated from the universal resistance formulae and diagrams for circular pipes. Results verify that the two new parameters Kazemipour introduces are more representative than those used by other investigators and offer solutions more rational than those previously proposed.