Hypersonic Vehicle Thrust Sensitivity to Angle of Attack and Mach Number

A new control-oriented scramjet engine model has been developed, named the MichiganAFRL Scramjet In Vehicle model (MASIV); it is used to compute thrust sensitivity to variation in flight conditions. The model solves conservation equations in 1-D, using several modeling techniques to retain some of the fidelity of higher-order simulations. A number complex physical processes are modeled (including jet mixing and finite rate chemistry) by a combination of ordinary dierential equations and algebraic scaling laws. The axial evolutions of the various flow quantities are computed in a short time, relative to computational fluid dynamics solutions. Although there is some loss of accuracy when using Reduced Order Models (ROMs), MASIV computes the overall performance of the flow path with respect to vehicle dynamics (thrust and drag) at an acceptable level for preliminary design and for use as a submodel for control design and evaluation. The model is exercised to predict the sensitivity of the thrust to variations in Mach number and angle of attack, and to compute the operating envelope of the engine.