一种多热力循环组合发动机进气道设计方案

针对马赫数0~6的预冷涡轮+冲压组合多热力循环发动机的宽范围工作要求，提出了一种在马赫数2~6范围内流量系数为1.0的宽范围轴对称进气道变几何调节方案，通过中心锥与分流板的协同平移运动，可在满足涡轮与冲压两通道流量分配要求的同时，实现两通道压缩量的匹配调节。对起始半锥角分别为20°和13°的两种变几何进气道方案开展了设计与对比研究。结果表明：起始半锥角对最终方案设计影响最大，起始半锥角为13°的进气道方案较起始半锥角为20°的方案，冲压通道和涡轮通道在来流马赫数为6时临界总压恢复分别提高了16%和14%，最大迎风面积减小了12.4%，但中心锥和分流板平移调节距离分别增加84%和91%。

Design scheme of combined multiple thermodynamic cycle engine inlet

To satisfy the requirement of wide range operations for the pre-cooling turbojet + ramjet combined multiple thermodynamic cycle engine with Mach numbers from 0 to 6, a variable geometry adjustment scheme of an axisymmetric inlet with full flow capture ability within Mach number from 2 to 6 is proposed. The mass flow distribution and compression requirement between the turbojet and ramjet passages can be met simultaneously by moving the center cone and the splitter plate. In this paper, the scheme design and comparative study of two variable geometry inlets with initial half cone angles of 13° and 20° respectively are conducted. The results show that the initial half cone angle affects the design of the final scheme most. The inlet scheme with an initial half cone angle of 13° is advantageous over the one with an initial half cone angle of 20° in that the critical total pressure recovery in ramjet and turbojet channels increase by 16% and 14% respectively when the free stream Mach number is 6, and the maximum windward area decreases by 12.4%. However, the moving distances of the center cone and the splitter are increased by 84% and 91% respectively.