A mechanistic fog inerting model has been developed to account for the effects of fog on the upward lean flammability limits of a combustible mixture based on the thermal theory of flame propagation. Benchmarking of this model with test data shows reasonably good agreement between the theory and the experiment. Applications of the model and available fog data to determine the upward lean flammability limits of the H2–air–steam mixture in the ice condenser upper plenum region of a pressurized water reactor (PWR) ice condenser containment during postulated large loss of coolant accident (LOCA) conditions indicate that combustion may be suppressed beyond the downward flammability limit (8 percent H2 by volume).

Issue Section:
Heat Transfer in Manufacturing
Keywords:
Combustion, Fire/Flames, Modeling and Scaling
Topics:
Combustion, Condensers (steam plant), Containment, Flames, Hydrogen, Ice, Pressurized water reactors
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