Nitrogen fire extinguishing system has a significant development space in the modern fire extinguishing because of its environmental protection, energy saving and high stability. To further broaden the application field of nitrogen fire extinguishing system, a shrinkage size model was used as the research object and combined with simulated flow field analysis. A nitrogen fire extinguishing system was characterized for alcohol fire extinguishing efficacy using nitrogen injection pressure as a variable and parameters such as extinguishing time, oxygen concentration, and temperature. Furthermore, diesel and gasoline were used as combustible materials to verify the extinguishing efficacy of pressure variation on Class B oil pool fires. It was found that with the increase of nitrogen injection pressure, the nitrogen extinguishing efficacy gradually increased and then leveled off in the confined space. The asphyxiating oxygen concentrations were 12.2 %, 13.2 % and 13.7 % for ethanol, diesel and gasoline, respectively. Asphyxiating oxygen concentration above limiting oxygen concentration (LOC). For extinguishing Class B oil pool fires in confined spaces, nitrogen extinguishing systems showed excellent fire extinguishing efficiency. They had specific application prospects in the field of protecting underground oil storage tanks and oil wells.

中文翻译：

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氮气灭火系统压力变化下B型油池火灾密闭空间窒息效应分析


氮气灭火系统因其环保、节能、稳定性高等优点，在现代灭火中具有重要的发展空间。为进一步拓宽氮气灭火系统的应用领域，以收缩尺寸模型为研究对象，并结合模拟流场分析。使用氮气喷射压力作为变量和灭火时间、氧气浓度和温度等参数，对氮气灭火系统的酒精灭火效果进行了表征。此外，柴油和汽油被用作可燃材料，以验证压力变化对 B 类油池火灾的灭火效果。研究发现，随着注氮压力的增加，氮气灭火效果在密闭空间内逐渐增加，然后趋于平稳。乙醇、柴油和汽油的窒息氧浓度分别为 12.2 %、13.2 % 和 13.7 %。窒息氧浓度高于极限氧浓度 （LOC）。对于在狭窄空间内扑灭 B 类油池火灾，氮气灭火系统表现出优异的灭火效率。它们在保护地下储油罐和油井领域具有特定的应用前景。