Leading-edge receptivity to fast and slow acoustic waves of boundary layers on a cylinder-wedge geometry is investigated for a set of six different cases with Mach number ranging from 3.0 to 7.3, through direct numerical simulations of the Navier-Stokes equations. The structure of the disturbance field transmitted downstream of the shock by the imposed freestream waves is analyzed, as well as the characteristics of the wall response and it sensitivity to the angle of attack and the freestream-wave inclination angle. The results show that different post-shock wave structures are formed for fast and slow acoustic waves, consisting of high-amplitude dragged and reflected waves for the fast-wave case, and oflow-amplitude convected waves for the slow-wave case. A good agreement is found withlinear interaction theory. The wall response along the wall for fast waves shows a strong resonant amplification of mode F in the nose region, and a modulated long-wavelength behavior further downstream. In contrast, the response to slow waves shows an initial decay in the leading-edge region, and an overall lower amplitude. The simulation results enable freestream disturbances, which are difficult to measure directly in experiments, to be related to wall pressure fluctuations.
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