水反应金属燃料在水蒸气环境下的稳态燃烧特性

Steady-state combustion characteristic of hydro-reactive metal-rich fuel in steam atmosphere

为探索高金属含量水冲压发动机的稳态燃烧机理,开展了镁基高金属含量水反应金属燃料在水蒸气氛围下的稳态燃烧试验研究,燃料中金属镁含量高于70%。采用直径0.5 mm的K型热电偶测量燃料燃烧波曲线,并拍摄了火焰图片。结果显示,工作压强2.0 MPa时,燃料稳态燃烧的燃面温度约为900.1℃,气相平衡火焰温度约为1 214.9℃;燃烧火焰明亮并紧贴燃面,没有颗粒燃烧形成的火星或轨迹。分析总结了镁基高金属含量水反应金属燃料在水蒸气氛围下的稳态燃烧特性,认为镁颗粒在燃面以熔融状态存在,并与水蒸气在燃面附近进行剧烈的放热反应,水蒸气向燃面的扩散过程是稳态燃烧的关键。

Combustion experiment of magnesium-based hydro-reactive metal-rich fuel in steam atmosphere was carried out in order to study the combustion mechanism of metal-rich water ramjet.The metal content of fuel is more than seventy percent.Combustion wave was measured by the thermocouple with 0.5 mm in diameter,and the photograph of flame was captured.The experiment results show that the combustion surface temperature is about 900.1 ℃ and the final gas phase flame temperature is about（1 214.9 ℃ at the operating pressure of 2.0 MPa.The gas phase flame is bright and near to the surface with no spark and track of particles.It was thought that magnesium particles are melt with the surface temperature,and reacted with steam near the surface.The diffusion of steam is the key process of steady-state combustion.