甲烷摩尔分数及初始压力对甲烷/RP-3航空煤油混合燃料燃烧特性的影响

采用定容燃烧实验装置获得初始温度为450K、初始压力为0.1~0.3MPa、当量比为0.7~1.5以及甲烷摩尔分数为0~0.8工况下甲烷/RP-3航空煤油混合燃料火焰发展特性图片、马克斯坦长度和层流燃烧速度等燃烧特性,分析甲烷摩尔分数及初始压力对甲烷/RP-3航空煤油混合燃料燃烧稳定性及层流燃烧速度的影响。结果表明:当量比为1.3时,随着甲烷摩尔分数增加,甲烷/RP-3航空煤油混合燃料燃烧趋于稳定,初始压力对燃烧稳定性影响较大,随着初始压力增加,燃烧稳定性变差。混合燃料马克斯坦长度随当量比增加而减小,当甲烷摩尔分数增加时,混合燃料马克斯坦长度减小趋势变缓,当初始压力增加时,混合燃料马克斯坦长度减小趋势明显变缓。混合燃料层流燃烧速度随当量比增加呈现先增大后减小的变化趋势。当甲烷摩尔分数为0、0.4和0.6时,随着甲烷摩尔分数增加,混合燃料层流燃烧速度逐渐增大,当初始压力为0.1、0.2、0.3MPa时,随着初始压力增加,混合燃料层流燃烧速度显著降低,随着甲烷摩尔分数和初始压力的增加,混合燃料层流燃烧速度峰值有向当量比大的区移动的趋势。 

Effects of methane mole fraction and initial pressure on the combustion characteristics of methane/RP-3 kerosene mixture

The combustion characteristics such as flame propagation characteristic, Markstein length and laminar burning velocity of methane/RP-3 mixture were obtained in a constant volume chamber at initial temperature of 450K, initial pressures of 0.1-0.3MPa, equivalence ratios of 0.7-1.5 and methane mole fraction of 0-0.8, and the effects of methane mole fraction and initial pressure on combustion stability and laminar burning velocity of methane/RP-3 mixture were analyzed. The results showed that at the equivalence ratio of 1.3, with the increase of methane mole fraction, the combustion of methane/RP-3 kerosene mixture became stable. The effect of initial pressure on combustion stability was greater. With the increase of initial pressure, the combustion stability of the mixture became worse. Markstein length of the mixture decreased with the increase of equivalence ratio. With the increase of methane mole fraction, the decrease tendency of Markstein length became slow, and with the increase of initial pressure, this decrease tendency became slow significantly. The laminar burning velocity of the mixture increased first and then decreased with the increase of equivalence ratio. At methane mole fraction of 0, 0.4 and 0.6, with the increase of methane mole fraction, the laminar burning velocity of the mixture increased gradually. At initial pressure of 0.1, 0.2, 0.3MPa, with the increase of initial pressure, the laminar burning velocity decreased evidently. With the increase of methane mole fraction and initial pressure, the peak value of laminar burning velocity of the mixture had the trend to move towards the fuel-rich zone.