中文摘要：

发展了一种进口型线水平投影可控的三维变截面内收缩进气道设计方法。基于反正切马赫数分布基准流场,在指定进口型线水平投影为椭圆和出口为圆的条件下,结合流线追踪和截面渐变技术设计了光滑过渡的内收缩进气道。在设计点（M_（ai）=5.4）和接力点（M_（ai）=4.0）对其进行数值仿真,计算结果表明,设计点时进气道的主要流动特性与基准流场基本一致,无黏时可以捕获98%的自由来流,喉道性能与基准流场基本相等。相对椭圆进口进气道,截面渐变的椭圆转圆进气道流场结构相似且性能下降较小,有黏条件下设计点和接力点时喉道总压恢复系数分别降低了2.9%和1.2%。此外,该进气道表现出良好的总体性能,接力点的流量系数达0.82。

英文摘要：

A design method is developed for three-dimensional variable section inward turning inlet with controlled horizontal projection of intake curve. Based on the basic flowfield with arc tangent Mach number distribution, the inward turning inlet with smooth shape transition from an elliptical horizontal projection of intake curve to a circular exit is designed utilizing stre- amline tracing and shape transition techniques. Numerical simulation is conducted at the design point （Mai = 5.4） and the re- lay point （Ma~ = 4.0）. The results indicate that the inlet is of the major features of the basic flowfield, and 98 % free incom- ing flow at the design point can be captured under the inviscid condition. The performance of the throat plane is close to the basic flowfield. In comparison with the inlet of elliptical intake, the variable section inlet with elliptical-to-circular transition has similar flowfield structure and slightly lower performance. Under the viscous condition, the total pressure recovery coeffi- cient of the throat plane reduces 2.9% and 1.2% at the design point and the relay point, respectively. In addition, the inlet has high overall performance, and the flow coefficient reaches 0.82 at the relay point.