南京航空航天大学硕士学位论文一种腹下S弯进气道地面和低速大攻角状态下气动特性研究姓名：翁小侪申请学位级别：硕士专业：航空宇航推进理论与工程指导教师：郭荣伟20080501南京航空航天大学硕士论文 i摘 要 本文利用具有吹/吸功能的进气道试验装置对一种腹下 S 弯进气道进行了地面工作状态和低速大攻角状态下的试验研究， 得到了该类进气道在地面工作状态和低速大攻角状态下的工作特性。同时为了进一步研究内通道的流动机理，对进气道在这两种工作状态下的气动特性开展了初步的数值仿真研究。研究结果表明： 1腹下 S 弯进气道在地面工作状态下，随出口马赫数的增加，总压恢复系数呈下降趋势，稳态周向畸变指数、紊流度和综合畸变指数均上升。出口马赫数0.45eMa =时，总压恢复系数为 0.842，稳态周向畸变指数为 0.467%，紊流度为 1.554%，综合畸变指数为 2.021%, 能够满足发动机的使用要求。 在低速大攻角状态下， 进气道性能参数变化规律与地面工作状态类似，总压恢复系数和综合畸变指数均有所提高。出口马赫数0.45eMa =时， 总压恢复系数为 0.881， 稳态周向畸变指数为 1.292%， 紊流度为 1.513%，综合畸变指数为 2.805%，满足进发匹配的要求。 2动态试验结果分析显示：在地面抽吸状态下，进气道出口的总压功率谱密度近似白噪声，内通道没有出现脱涡分离；在低速大攻角状态下，内通道可能发生了局部分离，出口总压功率谱密度在 220Hz 存在局部峰值，压气机部件的设计要考虑这一频率。 3与试验结果对比发现，本文的数值方法的计算结果与试验吻合的较好，表明本文采用的数值方法是可行的。仿真结果显示，在地面工作状态和低速大攻角状态下，进气道唇罩内侧发生了开式分离，分离涡导致进气道出口的总压较低，但畸变也较小。 关键词关键词：腹下 S 弯进气道, 地面工作状态，低速大攻角，总压恢复，畸变指数，功率谱密度，开式分离，数值仿真 南京航空航天大学硕士论文 iiABSTRACT Experiments of the flow in a ventral S-shaped inlet were carried out and described in this thesis, in which the inlet was tested under ground running and at high incidence and low speed respectively. Also, in order to explore the characteristics of the flow within the inlet, a numerical study was performed and compared with the experimental data. The results show that: 1. Under ground running, when the Mach number Mae of the flow at the exit increases, the total pressure recovery decrease, and the circular steady total pressure distortion, turbulence intensity and synthesis distortion increase. When Mae =0.45, the total pressure recovery coefficient equals 0.842, circular steady total pressure distortion coefficient equals 0.467%, turbulence intensity equals 1.554% and synthesis distortion coefficient equals 2.021%, which indicates that the inlet is fit enough to the engine under ground running. At high incidence and low speed, the general aerodynamic performance is similar to that under ground running. When Mae =0.45, the total pressure recovery coefficient equals 0.881, circular steady total pressure distortion coefficient equals 1.292%, turbulence intensity equals 1.513%, and synthesis distortion coefficient equals 2.805%, which meet the requirement of the matching of engine and inlet. 2. The dynamic results show that: under ground running, the dynamic total pressure signals have analogy to the white noise, which indicates that there is no separations vortex flow in the inlet; at high incidence and low speed, the peek value of the power spectrum of the dynamic total pressure signals is mainly fastened on 220Hz, which must be considered for the design of the engine. And it is conformed that the flow separations occur within the duct. 3. In contrast with the experiment results, the reliabilities of the CFD are verified. The numerical results show that open separations occur near the inside wall of the cowl, which may result in that the total pressure recovery and distortion are both lower. Keyword: ventral S-shaped inlet; incidence; low speed; ground running; total pressure recovery; distortion coefficient; power spectrum; CFD 南京航空航天大学硕士论文 vi图表清单 图 1 腹下 S 弯进气道的应用.2 图 2.1 低速风洞及模型照片.6 图 2.2 回流式低速风洞概貌图.7 图 2.3 进气道模型（侧视图）.8 图 2.4 试验模型剖面图.8 图 2.5 模型剖分图.8 图 2.6 总压耙示意图.9 图 2.7 出口截面探针等环面积分布示意图.10 图 2.8 出口动态传感器示意图(顺流) .11 图 2.9 插值后总压探针分布示意图.14 图 3.1 进气道内通道沿程静压分布曲线.18 图 3.2 进气道出口总压恢复系数等值图谱.19 图 3.3 随 Mae的变化曲线.19 图 3.4 0随 Mae的变化曲线.19 图 3.5 随eMa的变化曲线 .20 图 3.6 W随eMa的变化曲线.20 图 3.7 1 号传感器处总压功率谱密度分布.21 图 3.8 2 号传感器处总压功率谱密度分布.21 图 3.9 3 号传感器处静压功率谱