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Salt Water Modeling of Fire Compartment Gravity Currents.


pdf icon Salt Water Modeling of Fire Compartment Gravity Currents. (496 K)
Fleischmann, C. M.; Pagni, P. J.; Williamson, R. B.

International Association for Fire Safety Science. Fire Safety Science. Proceedings. 4th International Symposium. July 13-17, 1994, Ottawa, Ontario, Canada, Intl. Assoc. for Fire Safety Science, Boston, MA, Kashiwagi, T., Editor(s), 253-264 pp, 1994.

Sponsor:

National Institute of Standards and Technology, Gaithersburg, MD

Keywords:

fire research; fire safety; fire science; salt water models; compartment fires; gravity current; backdraft; explosion hazards

Abstract:

In order to investigate the gravity current speed and the extent of its mixed region in backdraft experiments, a series of scaled salt water experiments were conducted. The scaling parameters are the Froude number, [equation], and the normalized density difference, betta=(rho0-rho1)/rho1, where 1 indicates initial conditions in the compartment (fresh) and 0 indicates conditions in the ambient (salt). The scaled compartment (0.3m x 0.15m x 0.15m) was fitted with a variety of end openings: full, slot, door, and window. Video and photo data indicate that the mixing layer which rides on the gravity current in the full opening case, expands to occupy nearly the entire current in the partial opening cases. Results for the scaled current height, h*=h0/h1 and v* respectively are: full (0.5, 0.44), slot (0.38, 0.32), door (0.33, 0.35), and window (0.29, 0.22). These data are independent of betta and are in good agreement with limit calculations from the literature.