Impact of noncondensible gases on molten-metal water explosion onset

Explosive interactions between molten metal (currently focused on aluminum) and water ale being studied to determine what causes robust triggers for explosion onset; to determine the extent of protection provided front various coatings; and to develop a fundamentally-based simple, cost-effective novel methodology for prevention. The work scope includes experimentation and mathematical modeling of the interactions between molten metals and water at various different coated and uncoated surfaces. Phenomenological issues related to surface wettability, gas generation from coatings, charring of coatings, inertial constraint, melt temperature, water temperature and external shocks ale being investigated systematically, to gauge their relative impact on the triggerability of surface-assisted steam explosions. The steam explosion triggering studies (SETS)facility was designed and constructed as a rapid-turnaround, cost-effective and safe means to address these phenomenological issues. Data from SETS tests have indicated that noncondensible gas (NCG) generation during paint pyrolysis plays a predominant role in explosion prevention. This paper describes results of studies on the impact of deliberate NCG injection on explosion prevention, via molten melt drops fee-falling into water, as well as Si-om tests using the SETS facility for studying entrapment-induced explosive boiling. SETS is also being used to obtain information on time-varying and integral amounts of NCCs generated from various paints. Relevant data are presented. Results of investigations provide compelling evidence on the positive role NCGs play on explosion prevention. It is noted that the results of this research al-e fundamental in nature and should be adaptable to other metals (e.g., steel, magnesium, nuclear, etc.) industries, also.