Interaction of Supersonic Expansion Flow with Boundary Layer in Unsymmetrical Duct

Abstract

Study of unsymmetrical supersonic flow is important not only for basic research in gas dynamics but also for applications such as to jet propulsion and analyses of turbomachines. In the present study, a shock tube was used to generate supersonic flows in an unsymmetrical duct. The generation and oscillation of a pseudo-shock wave due to the interaction of a supersonic expanding flow with a boundary layer developed on the duct wall were studied experimentally using pressure transducers, and also by taking schlieren or schlieren interferometric photographs. The observed pseudo-shock wave oscillated in the flow direction. Its oscillation frequency was determined from schlieren photographs and compared with that obtained from pressure measurements. In addition, the Navier-Stokes equations were solved numerically to obtain steady-state solutions of the corresponding flow field.