Unwanted combustion enhancement by C6F12O fire suppressant
Unwanted combustion enhancement by C6F12O fire suppressant
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DOI：
10.1016/j.proci.2012.06.050
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发表时间：
2013-01-01
影响因子：
3.4
通讯作者：
Meier, Oliver
中科院分区：
文献类型：
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作者：
Linteris, Gregory T.;Babushok, Valeri I.;Meier, Oliver
有几种药剂正在考虑取代CF3Br用于飞机货舱灭火。然而，在美国联邦航空管理局（FAA）的一项模拟气溶胶罐爆炸的性能测试中，当以亚惰性浓度添加替代品时，所有替代品都被发现比不添加任何添加剂时产生更高的压力上升，因此测试失败。热力学平衡计算以及具有详细反应动力学的完全搅拌反应器（PSR）模拟，对其中一种剂c6f120 （Novec 1230）进行了计算，以了解意外增强燃烧而不是抑制燃烧的原因。添加助剂后的高压上升取决于助剂的量，并且只有在燃烧室中可用氧化剂的很大一部分被消耗时才会发生，对应于燃料、氧气和助剂的化学计量比例。建立了c6f120在烃类空气火焰中反应的动力学模型。搅拌反应器模拟预测，在较高的药剂负荷下，c6f120的抑制效果对整体化学计量相对不敏感，药剂的边际抑制效果大大降低，因此混合物在与FAA试验相对应的广泛条件下仍然是可燃的。目前的研究结果与先前对C2HF5和CF3Br的分析一致，并支持这些分析，这些分析也在FAA测试中进行了评估。由爱思唯尔公司代表燃烧研究所出版。
Several agents are under consideration to replace CF3Br for use in suppressing fires in aircraft cargo bays. In a Federal Aviation Administration (FAA) performance test simulating the explosion of an aerosol can, however, the replacements, when added at sub-inerting concentrations, have all been found to create higher pressure rise than with no agent, hence failing the test. Thermodynamic equilibrium calculations as well as perfectly-stirred reactor (PSR) simulations with detailed reaction kinetics, are performed for one of these agents, C6F12O (Novec 1230), to understand the reasons for the unexpected enhanced combustion rather than suppression. The high pressure rise with added agent is shown to depend on the amount of agent, and can only occur if a large fraction of the available oxidizer in the chamber is consumed, corresponding to stoichiometric proportions of fuel, oxygen, and agent. A kinetic model for the reaction of C6F12O in hydrocarbon-air flames has been developed. Stirred-reactor simulations predict that at higher agent loadings, the inhibition effectiveness of C6F12O is relatively insensitive to the overall stoichiometry, and the marginal inhibitory effect of the agent is greatly reduced, so that the mixture remains flammable over a wide range of conditions corresponding to those of the FAA test. The present findings are consistent with and support the earlier analyses for C2HF5 and CF3Br, which were also evaluated in the FAA test. Published by Elsevier Inc. on behalf of The Combustion Institute.