采用斜坡凹槽稳焰器强化H_2超燃的数值研究

用迎风TVD格式求解三维多组分体系的全N S方程 ,化学反应源项采用点隐处理 ,H2 和空气的超燃模型用 11组分、 2 3步基元反应模型描述 ,得到了凹槽燃烧室不同截面组元、当量比、压力、温度等值线和速度场的分布。计算结果表明 :凹槽稳焰器的回流区可提供高温自由基 ,有助于超燃点火 ;火焰在凹槽内和凹槽后斜坡的尾迹中驻定。结果对定量认识凹槽H2 超燃流场、设计高效率和优化结构的一体化凹槽有着重要意义。

Numerical investigation on supersonic combustion of hydrogen enhanced by a cavity flame holder

The purpose is to understand the flow field of hydrogen supersonic combustion enhanced by an inclined cavity flame holder. Upwind TVD scheme was use to solve three dimensional reacting system descried by multi component fully Navier Stokes equations. The chemical source term was treated by an implicit approach. A chemistry model with 11 species, 23 elementary reaction steps was used to describe supersonic combustion of hydrogen. Contours of flow variables, such as pressure, temperature, equivalence ratio and species were demonstrated to show their distributions in the combustor. Velocity field demonstrates the size and position of recirculation zones. The results show that this inclined cavity can be as an igniter, as well as for flame stabilizing. Such information contribute to further understanding the flow field of hydrogen supersonic combustion, and are valuable for designing an high performance cavity flame holder in hydrogen fueled scramjet.