MINIMUM DRAG BODY DESIGN UTILIZING STATE-OF-THE-ART TURBULENCE MODELS AND (OPTIONAL) LAMINAR FLOW CONTROL FOREBODIES

UTILIZING AN EXISTING NUMERICAL MODEL OF COUPLED VISCOUS-INVISCID FLOW AROUND AXISYMMETRIC BODIES, THE DESIGN OF MINIMUM DRAG BODIES FOR ARBITRARY MACH AND REYNOLDS NUMBERS SHALL BE SOUGHT. STATE-OFTHE-ART TURBULENT BOUNDARY LAYER MODELS AND THE OPTION OF SPECIFYIG A LAMINAR FLOW CONTROLLED FOREBODY SHALL BE INCORPORATED. DUE TO THE COMPLEXITY OF THE VISCOUS-INVISCID FLOW INTERACTION MODEL, AN ITERATIVE DIRECT METHOD OF SEEKING THE MINIMUM DRAG CONFIGURATIONS SHALL BE EMPLOYER. IN THIS APPROACH VARIOUS GEOMETRICAL CONSTRAINTS ARE FIRST IMPOSED ON THE DESIGN. SUBSEQUENTLY, A DISCRETE NUMBER OF PARAMETERS WHICH CHARACTERIZE THE CONFIGURATION ARE PERTURBED WITH THE ERRORS (IN THE CONSTRAINTS) AND THE DRAG COEFFICIENT SENSITIVITY TO THESE CONFIGURATION PERTURBATIONS COMPUTED. UTILIZING THE SENSITIVITY MATRIX, THE CONFIGURATION IS MODIFIED UNTIL THE ERRORS ARE ZERO AND THE DRAG COEFFICIENT IS STATIONARY. MAINTENANCE OF MINIMUM DRAG AT OFF-DESIGN CONDITIONS SHALL BE ADDRESSED BY USE OF A (NO FLUID STORAGE) SUCTION/BLOWING BOUNDARY LAYER MASS TRANSFER SYSTEM. DURING PHASE I, THE PHASE II WORK PLAN SHALL BE FORMULATED INCLUDING EXPERIMENTAL VALIDATION TESTS AND APPLICATION OF THE APPROACH TO THREE-DIMENSIONAL BODIES.