Rapid phase transitions

Adding volatile phase on top of hot phase (or vice versa) resulting in rapid phase transition and overpressuring of vessel. 

Goldwire, Jr., H. C., H. C. Rodean, R. T. Cederwall, E. J. Kansa, R. P. Koopman, J. W. McClure, T. G. McRae, L. K. Morris, L. Kamppiner, R. D. Kiefer, P. A. Urtiew and C. D. Lind. 1983. Coyote series data rejwrt LLNL/NWC 1981 LNG spill tests, dispersion, vapor bum, and rapid-phase-transition. Lawrence Livermore National Laboratory Report UCID-I9953. Vol. 2. 

Another type of physical explosion can occur upon rapid vaporization of a liquid when contacted with a significantly hotter material (e.g., water added to vessel containing hot oil). This is also referred to as a rapid phase transition explosion. In addition to blast, physical explosions can also generate fragments when initially confined. 

Rapid Phase Transition Explosion Rapid vaporization of a liquid when contacted with a significantly hotter material. 

Liquefied material stored under pressure Rapid phase transition (boiling-liquidexpanding-vapor explosion or BLEVE)... 

RAPID PHASE TRANSITIONS FROM LIQUID TO VAPOR... 

III. Rapid Phase Transitions between Liquefied Natural Gas and Water.. .. H3... 

Events of this nature have been described by various terms, e.g., rapid phase transitions (RPTs), vapor explosions, explosive boiling, thermal explosions, and fuel-coolant interactions (FCIs). They have been reported in a number of industrial operations, e.g., when water contacts molten metal, molten salts, or cryogenic liquids such as liquefied natural gas (LNG). In the first two examples noted above, water is the more volatile liquid and explosively boils whereas, in the last example, the cryogenic liquid plays the role of the volatile boiling liquid and water is then the hot fluid. 

Rapid-phase transitions are events in which there is a very fast transformation from an initial phase to another, more stable phase. Of primary interest here are transitions from liquid to vapor, but the definition would still be applicable for other transformations such as those from vapor to liquid and liquid to solid. 

Explosive boiling is certainly not the normal event to occur when liquids are heated. Thus, the very rapid vaporization process must be explained by theories other than standard equilibrium models. For example, if two liquids are brought into contact, and one is relatively nonvolatile but at a temperature significantly above the boiling point of the second liquid, an explosive rapid-phase transition sometimes results. Various models have been proposed to describe such transitions. None has been... 

In the sections which follow, we have summarized the available facts for rapid-phase transitions in several systems of industrial interest ... 

These results stimulated a number of studies, both in industry (Conoco, Esso, Shell Pipeline) and in academia (University of Maryland, M.I.T.). The objective was, primarily, to delineate the mechanism that led to these explosive events. The results of many small-scale experiments, primarily conducted by Shell Pipeline Corporation and M.I.T., led to the hypothesis that the apparent explosion was, in fact, a very rapid vaporization of superheated LNG. Contact of LNG, of an appropriate composition, with water led to the heating of a thin film of the LNG well above its expected boiling temperature. If the temperature reached a value where homogeneous nucleation was possible, then prompt, essentially explosive vaporization resulted. This sequence of events has been termed a rapid phase transition (RPT), although in the earlier literature it was often described by the less appropriate title of vapor explosion. 

The terra explosion is used in most instances in this section rather than rapid phase transition in accordance with the literature in this area. 

A thermal explosion is the metal industry s term for explosive boiling or rapid-phase transition. ... 

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