Abstract: To explore the effects of the process of rapid removing plug from outlet on the unstart flows，the process of rapid removing cone from outlet of two dimensional high speed inlets were investigated using the unsteady numerical simulation. The inlet performance of rapid removing cone from different state points in a period of inlet buzz were compared. Results show that for the unstart flow induced by downstream choking，if the freestream Mach number is lower than the over-speeding self-starting Mach number，the starting feature of the inlet with different buzz states behaves differently during the rapid removing process of the plug. Whether the inlet can establish the normal flow is determined by the transient flow at the moment of removing the plug.

Key words: High speed inlets；Removing plug at export；Inlet restarting performance；Separation zone；Unsteady numerical simulation

摘要： 为了探寻出口快速撤锥过程对高速进气道起动性能的影响，对二元高速进气道出口快速撤锥过程开展了非定常数值仿真研究。对比了进气道在一个喘振周期中从不同状态点处进行快速撤锥所表现出的起动性能的差异。研究表明，当来流马赫数低于进气道的加速自起动马赫数时，对于高速进气道因出口堵锥节流所引起的不起动流态(喘振)，从不同喘振状态开始撤锥，进气道表现出不同的起动特性，而进气道最终能否顺利建立起动流态与快速撤锥时机的选取有关。

关键词: 高速进气道；出口撤锥；再起动特性；分离区；非定常数值仿真