高超声速有攻角锥飞行工况下迎风面波包的演化

飞行工况下由于壁温与来流温度之比较低，Mack模态的不稳定性会得到显著增强，因此Mack模态占主导的有攻角锥迎风面相对侧面可能会提前转捩。本文采用高分辨率直接数值模拟研究了高超声速有攻角锥在飞行工况下迎风面Mack模态的演化规律，Mack模态由迎风中心线附近的一个短时局部壁面吹吸激发。波包的空间分布和不同模态幅值沿流向的演化过程表明在有攻角条件下，Mack模态的演化过程与零度攻角锥边界层中的类似，基频共振是Mack模态最可能的转捩形式。

Temporal evolution of wavepackets on the windward side of an inclined hypersonic cone under a flight condition

Under flight conditions, the instability of the Mack mode will be significantly enhanced since the ratio of the wall temperature to the freestream temperature is usually low. Therefore, the boundary layer over the windward side dominated by the Mack mode may transit to turbulence earlier than the lateral side. In this paper, a high-resolution direct numerical simulation is used to study the evolution of the Mack mode on the windward side of a hypersonic inclined cone under a flight condition. The Mack mode is excited by a short-time localized wall-normal blowing-suction around the windward centerline. The spatial distribution of wavepackets and the axial evolution of the amplitudes of representative modes show that for an inclined cone, the evolution of the Mack mode is similar to that in the boundary layer over a zero-angle-of-attack cone, i.e., fundamental resonance is the most likely transition routine of the Mack mode.