Hypersonic flows over multi-ramp configurations

Abstract

The effects of attaching multiple ramps to the standard double ramp configuration along with variations in ramp angle, free-stream Mach number and surface temperature are discussed in this investigation. This study investigates the changes associated with shock wave boundary layer interaction (SWBLI) due to ramp induced flow breakdown and the flow field fluctuation with changes in flow characteristics and design. This type of ramp junctions typically features in re-entry vehicles, engine intakes, system and sub-system junctions, control surfaces, etc. Ramp junctions usually are associated with strong separation bubble that has significant upstream influence impacting the effectiveness of aerodynamic surfaces, engine performance, thermal behavior and stability. Computation studies are carried out using Second order accurate, finite volume RANS solver considering compressible laminar flow characteristics, with solver settings provided like experimental conditions as per literature. Comprehensive double ramp studies with suggestions on reducing the separation bubble size are invariantly considered in literature, however there has been no study in understanding the inclusion of additional ramps in such flow scenarios. At the end of this study it was evident that such complex junction needs detailed understanding on how they benefit or impact the overall design of the system. It also gave a very good insight on the nature of flow around such complex junctions and instills motivation for detailed experimental understanding.