Experimental Evidence of Capillary Interruption of a Liquid Jet

Abstract

We observe the gravity discharge of liquid through the short cylindrical tube of diameter of 2 mm and aspect ratio 2.5 and 10 attached to the underside of Mariotte bottle. When the hydrostatic head is reduced and approaches to a certain value, a laminar jet escaped from the nozzle is interrupted and the discharge is drop wise. The plot of the discharge rate as a function of hydrostatic head does not pass through the origin as predicted by Torricelli law for an ideal liquid. We attribute this feature to the energy losses related with creating a new free surface area of the jet. The measurements for water and aqueous ethanol solution are compared with theoretical predictions based on the modified Bernoulli equation with the interfacial energy density correction and good agreement is observed.