The extinguishment of propane cup-burner flames by a halon-replacement fire-extinguishing agent C₆F₁₂O (Novec 1230) added to coflowing air in normal gravity has been studied computationally and experimentally. The time-dependent, axisymmetric numerical code with a detailed reaction mechanism (up to 141 species and 2206 reactions), molecular diffusive transport, and a radiation model, is used to reveal a unique two-zone flame structure. The peak reactivity spot (i.e., reaction kernel) at the flame base stabilizes a trailing diffusion flame, which is inclined inwardly by a buoyancy-induced entrainment flow. As the volume fraction of the agent in the coflow is increased gradually, the total heat release increases up to three times due to unwanted combustion enhancement by exothermic reactions to form HF and CF₂O in the two-zone trailing flame; whereas at the base, the flame-anchoring reaction kernel weakens (the local heat release rate decreases) and eventually the flame blows off. A numerical experiment, in which the C₆F₁₂O agent decomposition reactions are turned off, indicates that for addition of inert C₆F₁₂O, the maximum flame temperature decreases rapidly due to its large molar heat capacity, and the blow-off extinguishment occurs at ≈1700 K, a value identical to that for inert gases previously studied, while the reaction kernel is still burning vigorously. The calculated minimum extinguishing concentration of C₆F₁₂O in a propane flame is 4.12 % (with full chemistry), which nearly coincides with the measured value of 4.17 ± 0.30 %.

用哈龙替代灭火剂C ₆ F ₁₂扑灭丙烷燃烧杯火焰通过计算和实验研究了将O（Novec 1230）添加到正常重力下的气流中。具有详细的反应机理（多达141种和2206个反应），分子扩散传输和辐射模型的时变轴对称数字代码被用来揭示独特的两区火焰结构。火焰底部的峰值反应点（即反应核）使后随的扩散火焰稳定，该扩散火焰由浮力引起的夹带流向内倾斜。随着顺流中试剂体积分数的逐渐增加，由于放热反应形成HF和CF ₂引起的不希望的燃烧增强，总热量释放最多增加了三倍。在两区尾随火焰中的O; 而在底部，固定火焰的反应内核减弱（局部放热率降低），最终火焰被吹散。停止C ₆ F ₁₂ O试剂分解反应的数值实验表明，添加惰性C ₆ F ₁₂ O时，最大火焰温度由于其较大的摩尔热容和吹散而迅速降低。熄灭发生在≈1700K，与先前研究的惰性气体的值相同，而反应核仍在剧烈燃烧。计算出的C ₆ F _12的最小灭火浓度丙烷火焰中的O为4.12％（在完全化学作用下），几乎与4.17±0.30％的测量值一致。