燃烧器湍流射流火焰传热和柔性密封防火的实验研究

摘要

In order to avoid additional safety risk induced by cabin firewall seal flame penetration,impinging jet heat transfer was researched to the fireproof test oil burner,firewall temperature was investigated based on thermal conduct analysis and test temperature.After determine the cause of bellow seal fireproof failure, a light thermal gasket was developed by selecting suitable silicone rubber material and laying out special fibre.Thermal insulating effect of thermal gasket thickness(layer number)and square area was verified by test.The result shows that excess temperature of firewall without gasket is exponential growth during initial unsteady state,bellow was self ignited due to high temperature.Aramid fiber 1313 can help silicone rubber form dense and tough thermal shell,fabric inter-face will make turbulent which is energy dissipation,these will effectively insulate thermal.Meanwhile,thermal re-sistance will increase by cover with multilayer gasket whose inner hole is petal.the temperature will obviously de-crease and the flexible seal will pass fireproof test.%为避免火焰穿透防火舱密封造成额外安全风险,对防火实验用油燃烧器火焰的射流传热特性进行了研究.根据传热分析和实测温度探索了防火墙导热的温度变化规律.在分析波纹套密封防火实验失败原因后,通过选择合适硅橡胶材料,进行特殊纤维铺层布置,增设了轻质隔热垫.实验验证了隔热垫厚度(层数)和面积对隔热效果的影响.研究表明:无隔热防火墙过余温度在初始非定常阶段呈指数增长,高温导致波纹套根部自燃.芳纶1313纤维可促进硅胶形成致密强韧的绝热壳,织物界面可造成耗能的湍流,能有效隔热;同时通过覆盖足够面积花瓣式内孔的多层隔热垫,增加热阻,可明显降低背温实现柔性密封防火.