Correlation of Various Types of Axisymmetric Overflows of Small Vorticity

Abstract

Head and quantity observations of axisymmetric free overflow of water into straight-sided glass pipes were made during slow cyclic-flow transitions to observe the relation of head to discharge within the range of stable operating conditions for each of the various types of weir and orifice flow identified. These results have been combined with those of other investigators (on which this work has been based) to illustrate a correlation of the various coefficients of discharge in one or other of the following dimensionless forms: in order to eliminate the effect of temperature, which is not always quoted. The relation of ‘critical’ flow ( NFr(h) = 1) to the various results for overflow is also shown.