THE STABILITY CURVE OF NEWTONIAN LIQUID JETS

This article reports an experimental investigation on the disintegrati on of cylindrical jets through a study of the stability curve. We are interested mainly in the behavior of low-velocity jets in order to und erstand the development of the critical point, the first maximum on th e stability curve. The experimental results obtained for a jet of wate r under varying ambient pressures show that the critical point is not due to the effect of the aerodynamic forces for our working conditions . A detailed comparison. with other experimental measurements and with predictions deduced from models available in the literature is carrie d out and suggests a classification of the jet behavior according to t he ratio rho(G)/rho(G), where the critical density rho(G)* is a new j et parameter that is a function of the Ohnesorge number and of the len gth-to-diameter nozzle ratio. A new modification of Weber's equation i s suggested here in order to predict the critical velocity in any situ ation. The Hew model, tested for the experimental situations studied i n the present article, calculate critical velocity in good agreement w ith the experimental measurements.