INVESTIGATION ON DETECTION OF TRANSITIONING FLOWFIELDS

THE OBJECTIVE OF THIS PROGRAM IS TO DEVELOP AND FLIGHT TEST A UNIQUE MEASUREMENT SYSTEM THAT WILL PASSIVELY SENSE LAMINAR, TRANSITIONAL, AND TURBULENT BOUNDARY LAYER FLOW. THIS ADVANCED AERODYNAMIC FLOW SENSOR DESIGN INCORPORATES A THIN, SOLID-STATE POLYMER FILM THAT SENSES BOTH NORMAL AND SHEAR BOUNDARY LAYER FORCES. PRELIMINARY TESTS OF AN EIGHT SEGMENT SENSOR ARRAY POSITIONED ON THE WING OF A GRUMMAN AA-5 TEST PLANE YIELDED DATA THAT RESEMBLES THE CLASSICAL TOLLMIEN-SCHLICHTING WAVES THAT OCCUR IN THE BOUNDARY LAYER TRANSITION REGION MEASURABLE WITH HOT WIRES. INNOVATIVE DYNAMICS PLANS TO DEVELOP THIS TECHNOLOGY TO PRODUCE AN ADVANCED PASSIVE BOUNDARY LAYER TRANSITION DETECTION SYSTEM (BLTDS) THAT CAN OPERATE NONINTRUSIVELY AND RELIABLY THROUGHTHE SUBSONIC FLIGHT ENVELOPE. PROTOTYPE HARDWARE WILL CONSIST OF A PIEZOELECTRIC SENSOR ARRAY (PSA) AND A DATA PROCESSING & DISPLAY UNIT (DPU). THE SENSOR WILL BE DESIGNED TO BE A NONINTRUSIVE PSA STRIP WITH AN INTEGRATED TELEMETRY DATA LINK. THE DPU WILL BE DEVELOPED TO RECEIVE AND DIGITALLY PROCESS PSA DATA AND DISPLAY THE STREAMWISE BOUNDARY LAYER PROFILE IN A REAL-TIME OR AVERAGING MODE. DURING THE PHASE I PROGRAM, THE PROTOTYPE WILL BE INSTALLED ON THE NASA AMES-DRYDEN F-104/FTF FOR FLIGHT TEST AND CALIBRATION.