Peculiarities of 3-D Flow Development at Impinged and Swept Shock Wave/ Surface Interactions

摘要

Shock-wave/boundary-layer interactions (SWBLI) arise both in an external supersonic flow around various control surfaces of flying vehicles and in inlet ducts. Numerous situations with 3-D separated turbulent flows are especially complex and actively studied now. Accurate definition of their specific features and search of general properties are important for deeper understanding of their physics and development of computational models. Complex 3-D SWBLI are observed for example in the supersonic flow around the double-fin configuration (DF) mounted on a plate that models an inlet with three- dimensional compression and around the double-body of revolution (DR) over the surface. Interaction of swept crossing shock waves (SCSW) and expansion fans is realized in the first case. The second case is characterized by interaction of similar impinged disturbances with the surface. The objective of present study is a comparison of the features in development of such flows under a change of shock waves strength or a distance between the bodies. One of the effective techniques to specify the features of 3-D separation appearance and evolution is an analysis of the surface flow pattern visualization in the interaction regions (obtained by coating the test model surface with an oil film) because their topological properties can be theoretically grounded. For example a theorem is known that defines the number and type of singular points associated with separation and reattachment points as well as vortexes centers. Position of the coalescence and divergence lines which are associated with the boundaries of 3-D separation zones is defined by initial structure of these singular points.