飞机非金属燃油放沉淀阀耐火性能分析及验证

Analysis and verification of fire resistance of non-metal fuel water drain valve of aircraft

摘要:

非金属燃油放沉淀阀为飞机燃油系统设备，用于排出飞机油箱底部沉积的水和燃油。放沉淀阀通常安装于飞机外表面，按照适航条款的规定，其需要满足耐火要求。但传统的防火或耐火设计（选用耐高温的金属材料、喷涂防火涂料或面漆、采用防火的硅橡胶材料）对于放沉淀阀来说均不适用。为此，从非金属燃油放沉淀阀结构本身入手提高其耐火性，通过对不同主体厚度的放沉淀阀耐火性能进行瞬态热分析，研究放沉淀阀主体厚度对燃烧传热及燃油密封的影响，并通过试验验证分析结果。结果表明：在底部材料至少加厚至 13 mm 的情况下，放沉淀阀开始具备耐火性能，即在高温火焰燃烧的情况下，可以既不发生燃油的泄漏，亦不会发生燃油箱内温度超温的情况。

Abstract:

Non-metal fuel water drain valve installed on the outer surface of the aluminum wing tank near the nacle of the aircraft engine shall meet the fire resistance requirements in accordance with the provisions of the Airworthiness standards. The transient thermal analysis of the valve with different body thicknesses is carried out. The influence of the thickness of the valve body on the combustion heat transfer and fuel seal is analyzed, and the results are verified by experiments. The results show that when the valve body is thickened to at least 13mm, the valve begins to have fire resistance, that is, in the case of high temperature flame combustion, it can neither fuel leakage nor overtemperature in the fuel tank.