超燃冲压发动机内外流场三维燃烧数值模拟

以某型煤油燃料超燃冲压发动机整机模型为研究对象,对发动机外流场的流动与发动机内的流动燃烧过程开展了耦合三维数值模拟研究.燃烧室壁面静压计算结果与实验数据吻合良好,平均相对误差为4.9%,验证了数值方法的有效性.结果表明:内流场的流动燃烧状况既受到外流场捕获空气流量的限制,又会反过来影响着外流场的激波结构;泄压孔对保持发动机中各部件流量匹配起到关键作用;由于进气道内激波与边界层的相互作用以及泄压孔诱发的斜激波的影响,流场在第1处燃油喷射孔附近呈现出燃烧流场不对称特征. 

Three-dimensional combustion numerical simulation of scramjet internal and external flow fields

The coupling flow fields between internal combustion and external flow of a kerosene-fueled scramjet model were simulated by three-dimensional numerical methods. Good agreements between computation and experiments results are obtained for wall static pressure distributions of the combustor, of which the average relative error is 4.9%, validating that the numerical scheme employed is reliable. Results show that the combustion process of internal flow field is affected by air mass flow captured in the external flow field, and it in return influences the external shock wave structure. The pressure relief holes play a significant role in keeping mass flow matching between different components of the scramjet. In addition, flow filed near the first set of injectors was found asymmetric, due to the interaction between shock wave and boundary layer in the inlet as well as the oblique shock wave induced by the pressure relief holes there.