Flow Characteristics of Gradually Contracted Open Channel Flows

Abstract

Flow fields of gradually contracted open channel flows are measured by a Hot-film anemometer. Mean velocity profiles of the inner and the outer region are well expressed by the log-wake law. The wake strength parameter H decreases in the flow direction, and shapes of Reynolds stress distributions are slenderized than the universal distribution for a 2-D uniform flow. The turbulence energy is transformed into the mean flow energy, because the region, where the value of turbulence production is negative, exists. The intensity of the secondary flow decreases in the flow direction.