氢/氧气-气喷注器冷流掺混与燃烧比较的仿真研究

Simulation of cold flow and combustion characteristics of shear-coaxial GH_2/GO_2 injectors

分别采用无化学反应的和带化学反应的湍流N-S方程描述发动机内流动过程,对气-气同轴剪切式单喷注器进行了冷流掺混和燃烧的仿真.其中化学反应速率由Arrhenius公式计算,采用9步详细反应动力学模型来描述氢氧反应.对典型冷流和燃烧仿真结果进行了比较,结果表明燃烧掺混速率明显小于冷流掺混速率;并对同轴喷注器关键参数对冷流和燃烧掺混的影响进行了仿真和分析比较,得到速度比、缩进量和喷注流量的影响是一致的,而喷注速度的影响是相反的.

Single-element shear-coaxial GH2/GO2 injectors were simulated with nonchemical N-S equations for cold flow conditions and chemical N-S equations for combustion conditions. The chemical reaction was modeled with Arrhenius formulation. Detailed 9-step chemical dynamic model was used to describe the reaction of hydrogen and oxygen. The simulated results of typical cold flow fields and combustion fields were compared, showing that the mix ratio of combustion is much smaller than that of cold flow. The influences of velocity-ratio, recess-length and injector-flux for the cold flow condition are consistent with those for the combustion condition, while the influences of injection-velocity are contrary to each other.