超音速分离线喷管内流场数值模拟

Numerical simulation of supersonic splitline nozzle flow field

采用数值方法求解超音速分离线(SSSL)喷管内流场,研究了不同摆角对喷管流场分布的影响,对比分析超音速分离线与亚音速分离线喷管的轴向推力、径向推力及偏转放大因子随喷管摆角的变化规律,为超音速分离线喷管的设计研究提供理论参考。计算结果表明,摆动对超音速分离线喷管内流场影响显著,随着摆角的增大,内流场的非对称性和激波强度均增加;在相同摆管的轴向力分力略有减小,而径向分力则呈现增大的趋势;超音速分离线喷管与亚音速分离线喷管的径向分力比值,即偏转放大因子则随喷管摆角呈先增大、后减小的变化规律,本算例中的最佳放大因子1.36,对应的喷管摆角为2.5°;另外,随着摆角增大,超音速分离线喷管内流场Al2O3粒子分布的非对称特性也逐渐加强,活动体小端局部范围粒子浓度显著增大。

The numerical method has been used to solve the flowfield parameters of the Supersonic Splitline Nozzle.The effect of different angles on the flow field distribution of the nozzle has been studied.The axial thrust,radial thrust and amplification factor of the Supersonic Splitline Nozzle and Subsonic Splitline Nozzle are compared and analyzed.It provides a theoretical reference for the design of the Supersonic Splitline Nozzle.The results show that the effect of the deflection on the flow field in the Supersonic Splitline Nozzle is significant.With the increase of the deflection angle, the asymmetry and shock intensity of the internal flow field are increased. Under the same deflection angle, compared with the Subsonic Splitline Nozzle,the axial force component of Supersonic Splitline Nozzle slightly is reduced,whereas the radial force component presents an increasing trend.The ratio of radial force is called the amplification factor.The amplification factor is 1.36 and the corresponding angle is 2.5 degrees.In addition, as the angle of the nozzle increases,the asymmetry of the distribution of the alumina particles in the flow field of the Supersonic Splitline Nozzle increases gradually.Meantime, the concentration of the particles near the small end of the moving subassembly is significantly increased.