Computation of transonic flow around a 65-degree sharp-edged, cropped delta wing undergoing a forced pitching oscillating is carried out using the unsteady, compressible, full Navier-Stokes equations. The implicit, upwind, flux-difference splitting, finite-volume scheme is used with time-accurate stepping. A fine, O-H grid of 125x85x84 points in the wrap-around, normal and axial directions, respectively, is used. The wing mean angle of attack is 20° and the freestream Mach number and Reynolds number are 0.85 and 3.23xl0~6, respectively. The wing is forced to oscillate in pitch around an axis at the 0.25 root-chord station with an amplitude of 4° and a reduced frequency of π. The results for the initial conditions show a system of shock waves consisting of a ray shock under the primary vortex and a transverse terminating shock through which the primary vortex core experiences a breakdown. During the pitching oscillation, the terminating shock and vortex breakdown behind it oscillate. Moreover, the lift coefficient decreases as the angle of attack approaches its maximum value (shock moves upstream) and increases as the angle of attack approaches its minimum value (shock moves downstream).
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