Experimental study of the impingement of a liquid jet on the surface of a heavier liquid

Abstract

This study is concerned with the phenomenon of a liquid jet impinging normally on the surface of a heavier immiscible liquid. In essence, the work is a continuation of a previous investigation which involved an air jet impinging on a water surface.An analytical model is presented which relates the velocity of the jet in the neighbourhood of the interface to the depth of cavity created by the jet. The effect of interfacial tension is taken into account. Numerous experiments were conducted utilizing both circular and plane jets. An oil jet impinging on water and a water jet impinging on carbon tetrachloride were studied. The resulting experimental data were analysed in terms of the dimensionless quantities obtained from the analytical model.Results obtained from the circular-jet experiments were in close agreement with the results of the previously conducted air-water tests. However, there were some discrepancies in the plane-jet results; side-wall boundary-layer effects may be the explanation. Depending on the relative values of the Froude and Weber numbers, interfacial tension may be important in determining the depth of cavity created by a jet. Finally two intriguing phenomena, viz. interfacial shearing and cavity oscillation, were observed in the plane-jet experiments.