An Accurate, Unsteady Hybrid Flow Field Approach for High Altitude Maneuverability

Accurate prediction of aerodynamic thrust augmented maneuver forces, plume flow fields, and resulting signatures is a critical part of assessing the performance of defensive missile systems. These flow fields can contain both continuum and rarefied flow regimes that dynamically change during maneuvers. Current modeling techniques often need significant amounts of computational time to provide accurate representations of the flow fields and the observable signatures associated with such maneuvers. A hybrid method that automatically couples continuum and rarefied models to represent all regions of the flow would reduce the necessary computational time and increase responsiveness to customers while producing highly accurate flow field, force and signature predictions. The existing hybrid Modular Particle-Continuum (MPC) method has extensively been demonstrated to reproduce full steady-state rarefied flow predictions at a fraction of the cost. This effort will extend the method to model transient maneuver flow fields. In Phase I, SSI will establish the algorithms needed for this new transient flow MPC capability. In Phase II, the Phase I method will be further extended, verified, and validated. The capabilities will be integrated into existing DoD plume flow field modeling software.