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Flow of Alternative Agents in Piping.

pdf icon Flow of Alternative Agents in Piping. (545 K)
Cleary, T. G.; Grosshandler, W. L.; Yang, J. C.

Halon Options Technical Working Conference. Proceedings. HOTWC 1994. May 3-5, 1994, Albuquerque, NM, 105-115 pp, 1994.


halons; pipes; nacelle fires; fire protection; aircraft engines; fire suppression; fire extinguishing agents; halon alternatives


As part of the USAF, Army, Navy and FAA sponsored halon replacement project, the pipe flow characteristics of selected alternative agents for engine nacelle fire protection are being studied. Due to the remote location of the agent storage bottle, piping is required to transport the agent to various locations in an engine nacelle. The pipe flow from an agent bottle is characterized as a transient, two-phase flow. Since the selected alternative agents have thermo-physical properties different from halon 1301, the flow characteristics will be different, which may require system design changes. An experimental apparatus to study the flow characteristics of the alternative agents was designed and is described. A key feature of the experimental set-up is the ability to provide a constant heat in the simulated storage bottle. This will allow quasi-steady state pressure drop data to be gathered. It may then be possible to use the quasi-steady data to estimate the transient case. The pipe flow characteristics for different initial vessel temperatures and pressures, and pipe configurations will be examined. Preliminary results on the flow characteristics of HFC-227ea and halon 1301 are presented.