机载火焰抑制器传热特性影响因素研究

Effect Factors on Heat Transfer Characteristics of Airborne Flame Arrester

采用微元方法建立机载火焰抑制器耐烧过程数学模型,应用有限差分法对其进行数值计算,对比计算结果与实验数据,误差不超过10%。在此基础上,分析燃烧温度、阻火单元长度、壁厚及材料的导热率对火焰抑制器传热特性的影响。研究表明:阻火单元末端温度随燃烧温度升高而增加;阻火单元长度越长,其末端温度所达到的平衡温度则越低,耐烧性能越好;阻火单元壁面厚度的增加将导致其末端平衡温度的升高,耐烧性能下降;阻火单元材料的导热能力越强,其末端平衡温度越高,达到平衡的时间越短,从耐烧性能而言,提高材料的导热率是不利的。

The mathematical model of the airborne flame arrester in burning resistant process is set up by infinitesimal method,and the finite difference method is used for numerical calculation. The comparison between calculating results and experimental data displays that the deviation is within 10%. On this basis,the influences of burning temperature,flame arrester element length,thickness and thermal conductivity of material on heat transfer characteristic of flame arrester are analyzed. The study shows that the terminal temperature of flame arrester element rises with the increase of flame temperature. The length of flame arrester element is longer,the terminal equilibrium temperature is lower,and the burning resistant performance is better. The increase of thickness of flame arrester element causes the increase of terminal equilibrium temperature,and the burning resistant performance declines. The materials thermal conductivity of flame arrester element is better,the terminal equilibrium temperature is higher,and the time to reach balance is shorter. In terms of burning resistant performance,improving the thermal conductivity of material is unfavorable.