激波引燃冲压发动机一体化流场数值模拟

Numerical simulation of integrated flow field of shock-induced combustion ramjet engine

激波引燃冲压发动机是一种采用爆轰形式组织燃烧的吸气式高超声速飞行器动力系统。采用AUSMPW+迎风格式、氢氧7组分8步基于反应模型,在非结构网格离散域上求解二维多组分化学非平衡流Euler方程。采用发展的数值方法求解了激波引燃冲压发动机内外一体化流场,研究了台阶长度、斜劈尖角度对发动机流场结构和发动机性能参数的影响规律。计算结果表明,所发展的数值方法能用于激波引燃冲压发动机的一体化流场和性能预示计算;台阶长度和斜劈尖角度影响发动机流场结构和预混气体能量释放程度。推力和燃料比冲均随台阶长度的增大而增大,随斜劈尖角度的增大而减少。

Shock-induced combustion ramjet engine is an air-breathing hypersonic vehicle power systems by detonation combus-tion. In this paper, AUSMPW ＋ upwind scheme and 7 species 8 reaction kinetics model of hydrogen/oxygen were used, and the multi-component gas Euler equations with chemical reactions were solved in the unstructured computational domain. The integrated flow field was numerically simulated by using the numerical methods. The effects of bench length and oblique wedge angle on the flow field structure and performance of engine were studied. Results shows that：The methods developed in this paper can be used to simulate the integrated flow field and estimate the performance of engine;bench length and oblique wedge angle affect the flow field structure and energy released degree of premixed gas. The thrust and specific impulse of fuel increase with the increasing of the bench length, and decrease with the increasing of oblique wedge angle.