MEASUREMENTS OF TEMPERATURE AND PRESSURE IN UNDERWATER EXPLOSION BUBBLE

THIS PROPOSAL IS CONCERNED WITH THE DEVELOPMENT OF TRANSDUCERS THAT ARE CAPABLE OF PRESSURE AND TEMPERATURE MEASUREMENTS IN THE EXPANDING GASEOUS PRODUCTS OF UNDERWATER EXPLOSIONS. MEASUREMENT CAPABILITIES WILL BE IN EXCESS OF 100 KBARS AND 2500 DEG K WITH 1 MSEC OR BETTER TEMPORAL RESOLUTION. THESE TRANSDUCERS ARE EXPECTED TO RESOLVE THE TIMING OF THE REACTION OF METAL ADDATIVES IN THE EXPLOSIVES, THUS PROVIDING INFORMATION ON PERFORMANCE. THE APPROACH TO DEVELOPING THE TRANSDUCERS IS TO USE THIN FILM SENSORS INCORPORATED INTO RUGGED TRANSDUCER ARRANGEMENTS THAT ARE CAPABLE OF SURVIVING AN INTENSE INITIAL SHOCK WAVE. THIS WILL PERMIT LATER TIME TEMPERATURE AND PRESSURE MEASUREMENTS. THIN FILM SHOCK PRESSURE SENSORS IS A TECHNOLOGY WHICH IS WELL DEVELOPED AND PROVEN. THIN FILM PIEZORESISTIVE (CARBON) AND PIEZOELECTRIC (PVF2 AND VF2/VF3) SENSORS WILL BE USED FOR THE PRESSURE MEASUREMENTS. THIN FILM THERMORESISTIVE ELEMENTS (TANTALUM OR MOLYBDENUM ON A CERAMIC SUBSTRATE) WILL BE DEVELOPED AND USED FOR THE TEMPERATURE MEASUREMENTS. DEVELOPMENT OF THESE TRANSDUCERS, CAPABLE OF PRESSURE AND TEMPERATURE MEASUREMENTS WELL BEYOND THOSE CURRENTLY AVAILABLE, WILL EXTEND THE STATE OF THE ART IN HIGH PRESSURE AND TEMPERATURE TECHNOLOGY. THIS WILL ENABLE RESEARCHERS TO FURTHER THEIR UNDERSTANDING OF HIGH EXPLOSIVE PROCESSES.