Theoretical Model and Numerical Analysis for Asymmetry of Shock Train in Supersonic Flows

The reason for the asymmetry phenomenon of Shock/Boundary Layer Interactions (SBLI) in a completely symmetric duct with symmetric flow conditions is still an open question. A theoretical model for the asymmetry of shock train in supersonic flows is proposed based on the properties of fluid entrainment in the mixing layer and momentum conservation. Flow deflection angles downstream from different SBLI regions were deduced from this model. Steady numerical simulations were conducted to model the asymmetry of the SBLI in an isolator tested by Carroll. The obtained deflection angles using the theoretical model with the aerodynamic parameters from the numerical results of forced symmetric isolator flow give a larger range estimation and a close average value compared with the asymmetric full duct flow. This showed that the entrainment of shear layer on the separation induced by SBLI plays a dominant role in the asymmetry of the confined SBLI.