用均质流模型研究SF_6/Li燃烧体系

Study on SF 6/Li Combustion System Using the Model of Homogeneous Flow

基于均质流假设，研究了ＳＦ６气体与Ｌｉ液间的燃烧反应．在１０１．３２５Ｐａ（１ａｔｍ）下当反应体系处于相和化学平衡时，混合物分数可处理为唯一的状态变量，其他各状态变量表示为混合物分数的函数．分析了体系的密度、温度及各组分浓度对混和物分数的函变关系．按混合物分数的变化可得特征不一的５个状态区域：边界区、相变区、火焰区、冷凝区及核心区，讨论了各区域的特征．计算显示：当ＳＦ６气体与Ｌｉ液混合比接近化学当量比０．７２时，燃烧体系绝热燃烧温度达到最高值３５００Ｋ．最后讨论了熔池温度对燃烧体系热力学参数的影响：熔池温度越高，气相范围越大。

The combustion between gaseous SF 6 and molten lithium was studied based on homogeneous glow assumption. Under one atmosphere pressure, if the reacting system is in equilibrium the mixture fraction can be treated as the only independent parameter and the other parameters can be expressed as the functions of mixture fraction. The variation of system density, temperature and each species concentration with mixture fraction were also analyzed in detail. According to the variation of mixture fraction, five state zones of different features were obtained: boundary zone, phase transfer zone, plume zone, condensation zone and core zone. It is shown that when the mixture fraction is approaching to the stoichiometric value and the fuel is slightly dominated, the insulation temperature of combustion system reaches the highest value about 3 500 K. Finally, the effects of bath temperature on other thermodynamic state parameters were discussed: The higher the bath temperature, the greater span the gas phase exists, and accordingly, the smaller the value of mixture fraction at which the gas begins to appear is.