Penetration of vapor jets submerged in subcooled liquids

Abstract

An experimental investigation of the penetration distance required for complete condensation of a submerged turbulent vapor jet injected into a quiescent liquid bath of the same material was made. The bath was maintained in a subcooled condition at a temperature below the boiling temperature of the liquid at the bath pressure. The experiments were limited to choked injector flows with the penetration regime such that buoyancy effects are negligible. Tests were run for water, ethylene glycol, and iso-octane over a range of flow rates and bath pressures. A theoretical expression for the vapor penetration distance was developed utilizing a variable density single fluid model for the two-phase flow, with the turbulent mixing process treated by an entrainment law. Corrections for the external expansion of the choked flow beyond the injector exit were also determined. This model was found to correlate the results of both the present experiments and those of earlier investigators over a wide range of operating conditions and injector geometries. SCOPEThe injection of a condensing or reacting gas into a liquid bath occurs in a variety of industrial operations. For example, the condensing jet has been considered for direct contact feedwater heaters, underwater propulsion systems, and for the blowdown of primary nuclear boiler systems into a water bath, without releasing fissionable materials to the atmosphere. Reacting jets are of interest in metal processing and also for thermal energy sources involving submerged injection of an oxidizer into a liquid metal bath. Other applications involve dissolving a gas in a bulk liquid phase.The present investigation considers the condensing jet problem and relates only by analogy to the other processes mentioned above. In this instance, the vapor jet enters a liquid bath of the same material which is in a subcooled condition at a temperature below the boiling temperature of the liquid at the pressure of the bath. The most distinctive feature of this injection process is that the condensation of the vapor causes the gaseous portion of the flow to extend (penetrate) only a finite distance into the liquid. The penetration length of the vapor is an important factor in system design, since it is ordinarily desirable that condensation be completed within the liquid bath. Therefore, the major objective of the present investigation was to establish a correlation for predicting the vapor penetration length over a wide range of operating conditions. Past experimental work on this problem by Glikman The present investigation extends this earlier work by considering in addition to the steam-water system, the liquid-vapor systems of ethylene glycol and iso-octane. The experiments also employed a liquid bath contained in a closed vessel so that the influence of varying bath pressure could be investigated. As in earlier investigations, tests were conducted over a range of bath temperatures and injector flow rates, The experiments were limited to choked injector flows, however, in order to avoid t...

Experimental study on stable steam condensation in a quenching tank

“…However, the correlations for high-steam mass #ux conditions did not agree with each other. Weimer et al (1973) and Tsai and Kazimi (1976) investigated theoretically the steam jet lengths and proposed simple models for predicting steam jet lengths. However, it is shown that the prediction of steam jet length varies with the main assumptions employed.…”

“…Empirical correlations of the steam jet lengths were proposed by several workers (Chun et al, 1996;Kerney et al, 1972;Stanford et al, 1972;Weimer et al, 1973) for various steam mass #uxes and pool temperatures. However, the correlations for high-steam mass #ux conditions did not agree with each other.…”

Mixing Processes in High-Level Waste Tanks - Final Report

“…Many researchers have looked at the condensation of steam discharged into pools and many complex models have been developed to predict pressure oscillations and the distance required for complete condensation of the steam (Chun et al, 1996, Weimer et al, 1973, Kudo et al, 1974, Cumo et al, 1978, Tin et al, 1982, Simpson & Chan, 1982, Nariai & Aya, 1986. For our purposes the important result from this work is that the steam is (12) condensed over a short distance (0.4 to 1.5 times the vent diameter) so that we can look at the liquid exiting the condensation region for its effects on the pool thermal behavior (Fig.…”

Temperature fields induced by direct contact condensation of steam in a cross-flow in a channel

“…At high steam mass fluxes (near sonic and sonic), the steam forms either an oscillatory or a stable vapor jet that ends at a certain distance from the injector. Stable steam jets require choked injector flow and have been studied extensively, see Weimer et al [16] and Chen and Faeth [4]. At lower steam mass fluxes, the condensing steam forms a vapor pocket that continuously grows and collapses at the steam injection hole.…”