Abstract: In order to reach the goal of controlling flow coefficient on wide range of Mach numbers for a hypersonic inlet，an innovative method of pneumatic variable geometry has been performed. In this study，numerical computation was adopted. The compression section of a 2-D inlet generated elastic deformation by changing the pressure difference between its upper and lower surfaces，and then the flow coefficient at different Mach numbers could be controlled. The results of numerical computation indicate that when incoming flow Mach number is 4.5，5.0，5.5，the changing range of flow coefficient is 0.787～0.889，0.856～0.972，0.923～1.000，respectively. Compared with the fixed geometry inlet，the maximum flow coefficient is improved 14.2%，13.7%，7.4%，respectively，and the total pressure recovery coefficient is improved slightly. The results demonstrate that the method of pneumatic variable geometry is feasible and it can also realize the goal of controlling flow coefficient on wide range of Mach numbers.

Key words: Pneumatic variable geometry；Wide range of Mach numbers；Flow coefficient；Elastic deformation

摘要： 为实现采用气动变几何的设计思想使高超进气道在宽马赫数范围内控制流量系数的目的，针对二元进气道，采用数值计算的方法，通过改变压缩面的上下压差使压缩面产生弹性变形，从而控制不同马赫数下进气道的流量系数。数值计算结果表明，在非设计点来流马赫数为4.5，5.0，5.5条件下，流量系数的可控范围分别为0.787～0.889，0.856～0.972，0.923～1.000，各马赫数所对应的最大流量系数分别比定几何条件下提高了14.2%，13.7%，7.4%，并对出口截面的总压恢复系数也略有提升。由此证明，气动变几何的设计思想是可行的，可以实现在宽马赫数范围内控制流量系数的目的。

关键词: 气动变几何；宽马赫数范围；流量系数；弹性变形