An improved vibrating capillary device for producing uniform water droplets of 15 to 500 m radius

Abstract

A vibrating capillary device, consisting of a hypodermic needle vibrated at its resonant frequency by an electromagnetically driven diaphragm, produces controllable and very uniform streams of drops of radius down to 15 μm. The size and frequency with which the droplets are produced depend upon the flow rate of the liquid through the needle, the needle diameter, its resonant frequency and the amplitude of oscillation of the needle tip. The device is being used to study the collision and coalescence of small water drops in air.