EFFECT OF NOZZLE LENGTH ON GAS ENTRAPMENT CHARACTERISTICS OF VERTICAL LIQUID JET

For a vertical plunging liquid jet system using nozzles which had various values of the length-to-diameter ratio Lm/Dn, characteristics such as the bubble penetration depth Z and the gas entrainment rate Qg were studied experimentally in an air-water system. When nozzles of an Lm/Dn ratio exceeding 15 were employed, the values of Z and Qg were confirmed to be almost independent of Lm/Dn. Empirical correlations for predicting Z and Qg are also presented.