Parametrical Investigation of the Interaction Between Turbulent Wall Shear Layers and Normal Shock Waves, Including Separation

Abstract

The existence of strong shock waves plays a major role in the performance of modern aero-mechanical devices, since it is primarily responsible not only for the shock induced total pressure drop, but also for the increased shear layer losses due to flow separation. In this paper a fast energy-type integral method along with an approximate shock-turbulent shear layer interaction procedure are presented. This integral method, based on the two-zone model, is able to predict attached and fully detached shear flows. An extended turbulence model is also used in order to take the influence of the turbulence inside the interaction region better into account. The external flow pressure distribution results from an improved and extended form of an approximate small disturbance theory. A detailed investigation is carried out to estimate the influence of the inlet Mach number, the shear layer characteristics and the confinement of the geometry upon the static pressure field. The resulting method has been successfully applied to several test cases including ones where separation appears. Comparison between results of previous calculations, experimental data and results of the proposed method is also presented, along with the convergence history of the shear layer—shock wave interaction procedure. Finally, the method has been applied to one-stage high pressure supersonic flow compressor with normal shock appearance inside the rotor of the machine. The major conclusion drawn from the present work is that the shear layer characteristics (e.g., displacement thickness and form factor) have a dominant effect upon the flow field near the interaction region. Additionally, the proposed method requires no more than five overall iterations to reproduce the real flow field for all cases examined.