COMPUTATIONAL METHODOLOGY FOR MANEUVERING AIRCRAFT

THE PHASE I INVESTIGATION WILL DEMONSTRATE THE FEASIBILITY OF AN ANALYTICAL APPROACH TO PREDICT THE HIGH ANGLE-OF-ATTACK AERODYNAMIC CHARACTERISTICS OF AGILE FIGHTER AIRCRAFT AND TACTICAL MISSILES IN DYNAMIC MULTI-AXIS MANEUVERS. AN INNOVATIVE COMBINATION OF THEORY AND EXPERIMENT WILL PRODUCE IMPROVED MATHEMATICAL MODELS FOR THE DIRECT SIMULATION OF UNSTEADY AERODYNAMIC FORCES AND MOMENTS WHICH, WHEN COMBINED WITH A SIX-DEGREE-OF-FREEDOM EQUATION-OF-MOTION SOLVER, WILL HAVE THE CAPABILITY TO PREDICT FLIGHT TRAJECTORIES AND MANEUVERING PERFORMANCE OF MANEUVERING FLIGHT VEHICLES. THE PROPOSED COMPUTATIONAL METHOD, SUITABLY ECONOMICAL FOR PRELIMINARY DESIGN AND ANALYSIS PURPOSES, WILL BE APPLICABLE TO STUDY CONFIGURATIONAL EFFECTS ON UNSTEADY SEPARATED FLOWS AND THE SUBSEQUENT INDUCED DYNAMIC CHARACTERISTICS. THE UNSTEADY NONLINEAR AERODYNAMIC PREDICTION METHOD, INCLUDING PROPULSION EFFECTS, WILL BE CONSIDERED IN COMBINATION WITH A STRUCTURAL DEFORMATION MODEL TO PROVIDE A COMPLETE SIMULATION METHOD. EMPHASIS WILL BE PLACED ON (1) THE UNDERSTANDING AND MODELING OF THE PHYSICS OF COMPLEX FLOW PHENOMENA ASSOCIATED WITH FLOW SEPARATION, AND (2) AN ANALYTICAL PREDICTION METHOD WHICH DOES NOT REQUIRE A PRIORI KNOWLEDGE OF THE AERODYNAMIC CHARACTERISTICS FOR SPECIFIC CONFIGURATIONS. ANTICIPATED BENEFITS/POTENTIAL APPLICATIONS - SUCCESSFUL COMPLETION OF THE PHASE I FEASIBILITY STUDY AND DEMONSTRATION WILL LEAD TO A PHASE II EFFORT TO PRODUCE A SIMULATION METHOD FOR THE ANALYSIS OF FIGHT VEHICLES IN UNSTEADY MANEUVERS INVOLVING HIGH ANGLES OF ATTACK. THIS UNIQUE CAPABILITY WILL PROVIDE GREATER UNDERSTANDING OF THE PHYSICS OF THE COMPLEX UNSTEADY FLOW FIELDS AND IMPROVED ANALYSIS TECHNIQUES FOR FUTURE FLIGHT VEHICLES.