CHARACTERISTICS OF SUPERCRITICAL FLOW BELOW A SLUICE GATE IN A HORIZONTAL CHANNEL

Abstract

The characteristics of supercritical flow below a sluice gate in a horizontal rectangular channel are investigated both analytically and experimentally. For the developing flow, a method for calculation of the boundary-layer thickness and the water depth is examined and the relation between the boundary-layer development and the free-surface fluctuation is clarified. The relation between the loss of energy head and the energy thickness is presented by using an energy equation for the boundary layer. The results of the analysis are validated by experiments. For the developed flow downstream of the critical point, the experimental investigation reveals the position of the section where the velocity characteristics and the free-surface fluctuation are approximately equal to those of uniform open-channel flow.