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Modeling Study of the Behavior of Liquid Fire Suppression Agents in a Simulated Engine Nacelle.


pdf icon Modeling Study of the Behavior of Liquid Fire Suppression Agents in a Simulated Engine Nacelle. (306 K)
Fleming, J. W.; Yang, J. C.

Halon Options Technical Working Conference, 14th. Proceedings. HOTWC 2004. Sponsored by: 3M Specialty Materials, Boeing, Chemical Development Studies, Inc., DuPont Fire Extinguishants, Halon Alternative Research Corp., Hughes Associates, Inc., Kidde-Fenwal, Inc., Sandia National Laboratories, SEVO Systems, Next Generation Fire Suppression Technology Program. May 4-6, 2004, Albuquerque, NM, 1-10 pp, 2004.

Keywords:

halon alternatives; halons; fire suppression; nacelle engines; fire behavior; liquid fires; vaporization; evaporation; computational fluid dynamics; fire protection

Abstract:

This paper is a status report for a modeling study to evaluate the fire suppression potential for compounds in protecting engine nacelles. The project, "Vapor Loading and Suppression Effectiveness of Two-Phase Fire Suppressant", is part of the Strategic Environmental Research and Development Program (SERDP) funded DoD Next Generation Fire Protection Technology Program (NGP). The project seeks to assess the vapor concentration bounding conditions for condensed gases/liquids considering their physical properties and the intended application conditions. There is a high probability that gases or liquids with high boiling points, likely higher than that of Halon 1301, will be required to provide fire protection in engine nacelles. For this application, agents will need to be effective both at normal air temperatures near 300 K and also at low temperatures present at high altitude. In such a cold, non-trivial flow environment, the performance of the suppression agent will depend on a number of parameters including physical properties of the agent (heat capacity, boiling point, and heat of vaporization), the application temperature, and the flow-imposed time constraints for liquid agent evaporation. There is a need to eliminate compounds from consideration that will never be suitable and to identify those favorable properties that the successful agents are likely to possess. It is expected that the pre-qualified list will then undergo further scrutiny, including detailed modeling and experimental investigation. In this study, transport and evaporation of drops introduced into a simulated engine nacelle are treated using the NIST Fire Dynamics Simulator (FDS) version 3.