Large-eddy simulations and modal reconstruction of laminar transonic buffet

Transonic buffet refers to the self-sustained periodic motion of shock waves observed in transonic flows over wings and can limit flight envelope aircraft. Based on boundary layer characteristics at foot, has been classified as laminar or turbulent mechanisms underlying two have proposed be different (Dandois et al. , J. Fluid Mech. vol. 18, 2018, pp. 156–178). The effect various flow parameters (freestream Mach Reynolds numbers sweep incidence angles) an infinite wing (Dassault Aviation's supercritical V2C aerofoil) is reported here by performing large-eddy simulations (LES) for a wide range parameters. A spectral proper orthogonal decomposition identified presence low-frequency mode associated with high-frequency wake modes related vortex shedding. reconstruction based only former shows boundary-layer separation reattachment accompanying wave motion. modal suggests that bubble breathing phenomenon Dandois due this mode. Together, these results indicate physical governing are same. Buffet was also simulated zero incidence. Shock appear both aerofoil surfaces oscillate out phase each other indicating occurrence Type I (Giannelis Aerosp. Sci. Technol. 89–101) aerofoil. These suggest types