TBCC发动机用进气道设计及沿飞行轨迹斜板角度优化分析

Exploring TBCC Engine Inlet Design for Ma=5

基于Oswatitsch的最佳波系理论、Kantronitz准则和CFD技术,开展了TBCC发动机用二维混压式几何可调进气道的设计研究。基于一维气动热力学理论和CFD技术,完成了沿飞行轨迹斜板角度的优化和典型工作点上进气道特性的计算。计算表明,基于一维气动热力学理论、Oswatitsch最佳波系理论、Kantronitz准则和CFD技术,且有附面层抽吸设计的进气道能够满足沿飞行轨迹的TBCC发动机性能要求,并具有良好的内外特性。

We explore the TBCC （Turbine-Based Combined Cycle） engine inlet design for Mach number equal to 5, highest flight altitude equal to 26 kin, inlet total pressure recovery coefficient equal to 0. 520 55, engine mass flow equal to 331.88 kg · s^-1, and corrected mass flow equal to 150. 631 kg · s^-1. In the full paper we explain in some detail the results of our exploration. In this abstract, we just add some pertinent remarks to listing the two topics of explanation. The first topic is ： aerodynamic and geometrical design method for the inlet of TBCC engine. Its two subtopics are： the selection of an inlet design point （subtopic 1.1）, and the design method and geometry of inlet （subtopic 1.2）. In subtopic 1.1, we give the main parameters influencing TBCC engine inlet design and Fig. 1 in the full paper showing the flight trajectory of the aircraft carrying the TBCC engine. In subtopic 1.2, we design the geometry of the inlet, its internal contraction ratio being 5. 18, lower than that required by the Kantronitz limit. The second topic is： the characteristics of the inlet along flight trajectory and the analysis of ramp angles. Its four subtopics are： control equation, turbulence model, boundary condition and grid discretization （subtopic 2. 1）, the analysis of the flow field of the inlet on design point （subtopic 2.2）, the performance analysis of the inlet along flight trajectory （subtopic 2. 3）, the analysis of the flow field of the inlet at off-design points （subtopic 2. 4）. In subtopic 2.3, we adjust the three ramp angles and obtain the flow coefficient and the total pressure recovery coefficient of the inlet under the condition of different Mach numbers, summarized in Figs. 7 and 8. The analysis results show preliminarily that the boundary layer and shock interaction induce easier separation regions and that bleed slots improve the separation by eliminating low energy air from the core flow. Computational results show that the performance of the inlet designed by us can satisfy the requirements of the TBCC engine along flight trajectory.