Atomization of Liquids by means of a Rotating Nozzle : 3rd Report, On the Thicknesses of Liquid Jets

Abstract

This paper deals with the contraction of liquid jets under the actions of acceleration and surface tension force. At the beginning, the thickness of a jet discharged from a fixed nozzle is discussed, then with the results thus obtained for a guide, the formula for a jet from a rotating nozzle is derived : [numerical formula] where v_n=discharge velocity, l=distance on the jet from the nozzle, D=thickness of the jet at the point of distance l, D_n=diameter of the nozzle, [numerical formula] (called Weber number, γ=specific weight of a liquid and σ=surface tension) and α=acceleration variable with l, but when l is small α becomes nearly equal to a centrifugal acceleration Rω². All of the physical properties of a liquid are included in W_e as shown above, and when W_e exceeds the approximate value of 4, the effects of those properties on the thickness of a jet becomes negligibly small and the formula can be simplified as [numerical formula] The thickness of a jet discharged from a fixed nozzle can easily be obtained from these formulae, only replacing α with the acceleration of gravity g. All these formulae agree very well with the experimental results.