Scramjet Research with Flight-Like Inflow Conditions

Abstract

Abstract : Studies of flow distortion on fundamental scramjet flows have been performed using computational fluid dynamic (CFD) techniques, in conjunction with experimental studies in AFRL/RQH Research Cell 18 (RC18) and Research Cell 19 (RC19). Flow distortion is created in scramjet inlets during flight due to the effects of viscosity near the walls, the effects of shock waves caused by turning the flow, and by the interactions of the viscous boundary layers with shock waves. However, most fundamental scramjet experiments take place in direct-connect test facilities, without an inlet. To support the experimental study of distortion in these direct-connect facilities, CFD was used to design ground test hardware that would create shock waves and boundary layers consistent with flight inlets. Other studies were made on the interaction of these flow distortions with the fuel injection, mixing, and combustion. These studies provide the first detailed investigation of the interaction effects where detailed ground test data is available to validate the computational results. These results have provided key insights into the interaction effects, which will be used to guide the design of scramjet combustors that are tolerant of the anticipated distortion field.