一种高超声速进气道加速自起动的实验方法

为了探寻在地面常规暂冲式风洞中开展高超声速进气道加速自起动实验的可行性,提出了基于前遮板的高超声速进气道连续变攻角加速自起动实验方法。该实验方法通过将安装有前遮板的进气道模型在风洞实验段整体从极限正攻角旋转至极限负攻角,前遮板会产生激波对远前方气流减速,或产生膨胀波对远前方气流加速,而位于前遮板下游的进气道即可获得加速自起动过程所需连续加速的来流条件。通过数值仿真对所提出的加速自起动实验方法进行了验证。研究结果显示:以2(°)/s的角速度整体旋转基于前遮板的高超声速进气道模型,其起动马赫数与高超声速进气道自身加速自起动马赫数相差在1%以内,表明基于前遮板的高超声速进气道连续变攻角加速自起动实验方法能够被用于在常规暂冲式风洞中开展高超声速进气道加速自起动实验研究。 

A test method for accelerating self-start of hypersonic inlets

To explore the feasibility of testing the accelerating self-start ability of hypersonic inlets in a blow-down wind tunnel, a self-starting test method based on continuous varying attack angle of a shielding plate fixed on the upstream hypersonic inlets was developed. In the test, the hypersonic inlet, together with a shielding plate, rotated from the limiting positive attack angle to the limiting negative attack angle. The shielding plate decelerated the freestream by shock wave, or accelerated the freestream by expansion waves. Hence, the continuous accelerating freestream downstream the shielding plate can be obtained for the inlet. The test method was verified with numerical simulations. Results show that: the deviation of the starting Mach number in the rotating process of the hypersonic inlet with a shielding plate at an angular velocity of 2(°)/s and the inlet self-starting Mach number is within 1%, indicating that the method based on the continuous varying attck angle of a hypersonic inlet with a shielding plate can be used to test the self-starting ability of hypersonic inlets in a blow-down wind tunnel.