HIGH SPEED PARTICLE TRAJECTORY MEASUREMENT USING STEREO PHOTOGRAPHY

LAMINAR FLOW OFFERS SIGNIFICANT PAYOFF TO UNDERSEA VEHICLES BY PROVIDING DRAG REDUCTION AND REDUCED RADIATED NOISE. IT HAS BEEN SHOWN THAT SMALL PARTICLES CAN CAUSE LAMINAR FLOW TO BECOME TURBULENT. A TECHNIQUE IS NEEDED TO MEASURE THE TRAJECTORY A PARTICLE TAKES AS IT MOVES PAST AN UNDERWATER VEHICLE. THE DEVELOPMENT OF LASER SYSTEMS HAS PROVIDED A MEANS OF OBTAINING FLOWFIELD DATA, HOWEVER, THESE SYSTEMS ARE VERY SENSITIVE TO ADJUSTMENT AND ALIGNMENT, AND REQUIRE HIGHLY TRAINED PERSONNEL FOR OPERATION AND DATA ANALYSIS. A LESS SENSITIVE TECHNIQUE FOR OBTAINING QUANTITATIVE FLOWFIELD DATA IS NEEDED. THE WORK PROPOSED HERE WILL USE STERO PHOTOGRAPHY AND SPECIALLY DEVELOPED LIGHTING TECHNIQUES TO MEASURE A PARTICLE TRAJECTORY AND VELOCITY AS IT PASSES NEAR AN UNDERSEA VEHICLE. PHASE I COVERS THE DESIGN OF THE SYSTEM FOR STEREO PHOTOGRAPHIC ANALYSIS FOR THE TRACKING OF A PARTICLE PASSING NEAR AN UNDERSEA VEHICLE. THIS WILL INCLUDE DETERMINATION OF CAMERA REQUIREMENTS, DESIGN OF ILLUMINATION AND CONTROL POINT SYSTEMS, SPECIFICATION AND/OR DESIGN OF SUPPORT EQUIPMENT, AND A DETAILED PLAN FOR A PROOF-OF-CONCEPT TEST. PHASE II WILL BE USED TO ACQUIRE, FABRICATE, AND ASSEMBLE THE SYSTEMS PROPOSED IN PHASE I AND TO PERFORM THE PROOF-OF-CONCEPT TEST AND EVALUATION.