Reynolds-Averaged Navier-Stokes Simulations of Shock Buffet on Half Wing-Body Configuration

摘要

This paper presents a numerical study of transonic flow over a wing representative of a large transport aircraft. Reynolds-averaged Navier-Stokes simulations are conducted on a half wing-body configuration, with a Mach number close to cruise conditions and different angles of attack. The flow physics are discussed with particular attention to the separated zone induced by the shock wave. For small angles of attack, this zone is limited to the vicinity of the shock foot, and steady simulations converge. With increasing angle of attack, the separated region increases in size and begins to oscillate. This phenomenon, known as transonic shock buffet, is characterised by shock motions on the outboard section of the wing. In contrast to previous publications, three-dimensional shock buffet is reproduced by such unsteady simulation, and much information can be extracted analysing frequency content, location of unsteadiness and amplitude. The results provide an insight into the mechanism which is responsible for the onset of the unsteadiness.