FLOW CAHACTERISTICS OF PLUNGE FLOWS IN WELL-MIXED AND STRATIFIED RESERVOIRS

Abstract

Flow characteristics of plunge flows in well-mixed and stratified reservoirs are investigated experimentally. The study is directed towards the estimation of the densimetric Froude number F_p at the plunge point and the initial mixing rate γ. The internal critical slope I_c is found to be about 1/50. It is shown that the values of F_p in well-mixed reservoirs are strongly affected by the inflow densimetric Froude number F_o and the channel slope I when plunging takes place near the inlet of a reservoir, whereas Fp becomes a constant value of 0.5 in both mild and steep channels when these effects are less pronounced, and that for the range of I=1/150-1/30 is quantifed as a linear function of I. It is also found that the values of F_p in well-mixed reservoirs with a steep channel are also well approximated as 0.5 when F_o is more than about 2.0.