Effects of Horizontal Velocity Variations on Ultrasonic Velocity Measurements inOpen Channels

摘要

The report explores the differences in calculating average cross-sectionalvelocity from measured line velocity when the 1-D von Karman velocity profile is replaced by an equation that represents both vertical and horizontal effects of boundary friction. The relation between mean and line velocity derived from the equation, referred to as 2-D, is compared with the standard relation based on the 1-D von Karman velocity profile, which accounts for boundary friction effects only in the vertical direction. These two formulations are compared for the cross sections at the L-31N Canal and Snapper Creek Extension Canal and for various other channel geometries to evaluate the significance of the differences in these schemes on velocity determinations.