超声速进气道反压引起的不起动/起动现象研究

为了探索节流反压变化对进气道起动性能的影响,在来流马赫数为2.0的情况下,采用定常/非定常数值仿真方法对出口可移动壁面运动速率为12,24,36mm/s的进气道进行了研究,分析了不同可移动壁面运动速率引起的堵塞度变化对进气道流场特性及气动性能的影响。结果表明:采用非定常数值仿真获得的进气道性能参数和流场特性变化规律与定常数值仿真时一致,定常/非定常数值仿真时的进气道性能参数均存在"迟滞回路"现象;进气道出口堵塞度变化速率越大,"迟滞回路"现象越明显;堵塞度变化速率越大,进气道进入不起动状态时的堵塞度越高,进气道再次进入起动状态时的堵塞度越低。

Investigation on Unstart/Start Phenomenon of Supersonic Inlet Caused by Back Pressure

Steady/Unsteady numerical simulation study was performed at Mach 2.0 about unstart/start phenomenon of supersonic inlet caused by throttle characteristic. The effect of blockage change rate on inlet flow characteristic and performance were analyzed and three different change rates of blockage were considered. The results indicate that the change law of inlet flow characteristics and performance are similar in both steady and unsteady numerical simulations. The hysteresis loop of inlet performance occurs in numerical simulation process, and the larger blockage change rate is, the more obvious inlet performance hysteresis loop becomes. The value of unstart blockage increases and start value decreases with the rising of blockage change rate.