MINIATURIZED PARTICLE CHARACTERIZATION SYSTEM

THIS PROPOSAL DESCRIBES A PROGRAM TO DEVELOP A SYSTEM TO MEASURE THE SPATIAL AND TEMPORAL DISTRIBUTIONS OF PARTICLE SIZE, LIQUID WATER CONTRENT, AND VELOCITY AT THE ENGINE INLET OF ADVANCED AIRCRAFT. THE SYSTEM USES MINIATURIZED AND RUGGED COMPONENTS WHICH ARE CAPABLE OF ELECTRONIC FOCUSING ALLOWING IT TO MEASURE THE NEEDED DISTRIBUTION ACROSS THE INLET SPAN WITHOUT LMOVING THE PROBE ITSELF. AUTOMATIC ADJUSTMENT OF THE PHOTODETECTOR GAIN WOULD RESULT IN A PARTICLE SIZE DYNAMIC RANGE OF 400:1. A SECOND LEVEL OF TECHNOLGY IS ALSO PROPOSED TO COMPLEMENT THE PROBE MEASUREMENTS WITH INSTANTANEOUS PARTICLE DISTRIBUTION EVERYWHERE IN THE INLET. A LASER SHEET WOULD ILLUMINATE THE ENGINE INLET OR ANY OTHER CROSS SECTION ALONG THE DUCT, AND A 2-D MINIATURIZED DETECTOR SYSTEM WOULD IMAGE THE SCATTERED LIGHT DISTRIBUTION ONTO A CCD ARRAY. THE LASER SHEET MEASUREMENTS WOULD PROVIDE QUALITATIVE AND IN SOME CASES, QUANTITATIVE COMPARISONS OF THE DROPLET DISTRIBUTION ANYWHERE IN THE DUCT, AND WOULD ALSO INDICATE THE MOST STRATGEGIC LOCATIONS TO PLACE THE PARTICLE SIZING PROBE. PHASE I WILL INCLUDE ANALYTICAL AND EXPERIMENTAL RESEARCH WHICH DEFINE OPTIMUM STRATEGIES AND TEST THEM ON A BREADBOARD UNDER CONTROLLED CONDITIONS.