Magan Singh, Kartik Venkatraman
DOI Number: N/A
Conference number: IFASD-2024-176
Transonic shock buffet, or shock oscillations due to shock-induced boundary layer separation, over a finite span wing, is of considerable interest from the point of view of fundamental aerodynamics, as well aircraft performance in an overall sense. In this work, we present analyses from numerical URANS simulations of 3D transonic buffet flow over the Benchmark Supercritical Wing, a finite span wing. Transonic buffet is characterized by a broad band of frequencies and aperiodic aerodynamic response. Externally imposed pitch oscillations of the wing, at a frequency close to the transonic buffet frequency of the stationary wing, results in frequency entrainment of the lift and drag coefficients close, but not equal, to the externally imposed frequency. However, the pressure fluctuations as well as streamwise and spanwise pressure wave propagation occur at the transonic buffet frequency. Cross-correlation analysis of the unsteady pressure, on the suction surface, show wave propagation toward the leading edge upstream and downstream of the shock. All streamwise correlation plots confirm the shock oscillations at the buffet frequency of the stationary wing, which is also the frequency of expansion and contraction of the separation bubble.