论文标题
高速流动的轴对称体上的大和小振幅冲击波振荡
Large- and small-amplitude shock wave oscillations over axisymmetric bodies in high-speed flow
论文作者
论文摘要
在高速隧道中，以均匀的高速流量，以均匀的高速流量，以均匀的高速流量，以均匀的高速流量的锥形体上的自我维持的冲击波振荡现象在马赫数$ m = 6 $中研究了。流动和冲击波动力学由两个由身体的三个长度尺度提出的两个非二维几何参数决定，其中两个与锥形前体相关，一个与底座有关。这些实验中的时间分辨Schlieren图像揭示了流动中的两个不同冲击波振荡状态，并允许在两参数空间中映射不稳定边界。提出了物理机制来解释冲击波系统从稳定到振荡状态的振荡和过渡。与文献中报道的尖刺爆炸体上的冲击波振荡的规范单参数问题相比，本问题的两参数性质引入了流动动力学的不同元素。
The phenomena of self-sustained shock wave oscillations over conical bodies with a blunt axisymmetric base subject to uniform high-speed flow are investigated in a hypersonic wind tunnel at Mach number $M = 6$. The flow and shock wave dynamics are dictated by two non-dimensional geometric parameters presented by the three length scales of the body, two of which are associated with the conical forebody and one with the base. Time-resolved schlieren imagery from these experiments reveals the presence of two disparate states of shock wave oscillations in the flow, and allows for the mapping of unsteadiness boundaries in the two-parameter space. Physical mechanisms are proposed to explain the oscillations and the transitions of the shock wave system from steady to oscillatory states. In comparison to the canonical single-parameter problem of shock wave oscillations over spiked-blunt bodies reported in literature, the two-parameter nature of the present problem introduces distinct elements to the flow dynamics.
