Shock oscillation and fluctuation mechanisms of wall pressure on a V-shaped blunt leading edge

This paper studies the shock oscillation and the fluctuating behavior of wall pressure on a V-shaped blunt leading edge. Utilizing numerical simulation and the proper orthogonal decomposition technique, this study analyses the primary modes of shock oscillation and their effect on wall pressure for both a V-shaped blunt leading edge and an improved heat flux reduction configuration. The findings reveal that the shock interaction structures on these models are responsive to the downstream subsonic flow, thereby triggering two distinct oscillation modes: “swinging” and “breathing.” These modes drive the main shock interaction structure and the near-wall shock interaction structure in a quasi-periodic motion. Concurrently, the complex shock oscillation phenomenon exerts three distinct influences on wall pressure: the positional oscillation of the shock wave/boundary layer interaction structures, the instability of the shear layer bounding the supersonic jet, and the positional oscillation of the jet collision structure near the stagnation point. Furthermore, the study demonstrates that the improved heat flux reduction configuration is more effective at suppressing wall pressure fluctuations, indicating its potential value in designing hypersonic vehicles. This paper offers valuable insights into understanding shock oscillations and their effect mechanisms on wall pressure within hypersonic flows.