带凹腔钝头体第IV类激波干扰特性研究

Effects of Forward-Facing Cavity on Behaviors of Type IV

关键词:  高超声速流动  激波/激波干扰  带凹腔钝头体  振荡模式

Key words:  Hypersonic flow  Shock/Shock interaction  Blunt body with a forward-facing cavity  Oscillation modes

摘要:

采用激波风洞实验与数值模拟相结合的方法，对高超声速带凹腔钝头体的第IV类激波干扰非定常振荡特性进行了考察和分析。结果表明，随着入射激波与弓形激波相对位置的不同，第IV类激波干扰既可能出现稳定的波系干扰结构，也可能出现较为剧烈的非定常振荡现象。在实验条件下，观察到了高频前后振荡和低频上下振荡两种不同的振荡模式。数值模拟结果与实验吻合较好，超声速射流与凹腔的耦合作用在振荡过程中起到了关键作用。

Abstract:

The effects of blunt body with a forward-facing cavity on the unsteady behaviors of hypersonic type IV shock interaction were experimentally and numerically investigated . The results show that type IV shock interaction can be either steady or unsteady depending on the location of the oblique impinging shock/bow shock intersection point. Under the conditions within the current work，two different oscillation modes，namely high frequency forward-backward oscillation and low frequency up-down oscillation modes were observed. The numerical results agree fairly well with those of the experiments. The interaction between the supersonic jet and the forward-facing cavity plays a key role in the shock wave oscillations.