SBIR-STTR Award

The objective of this proposal is to develop a high-accuracy, high-range pressure and temperature transducer for the measurement of rapid transients to 700 mpa and temperatures to 3000 k, as well as heat transfer, in gun interiors. All three measuring functions will be performed by one small (about 20 mm in diamenter) sensor unit and some external temperature sensors. The pressure is detected by capacitive methods using a thick, rugged tungsten membrane. The sensor can operate at temperatures of 2500 k. The explosion temperature is simultaneously measured by a small high-accurary, high-speed radiation detector capable of withstanding temperatures of 2000 k and integrated in the pressure sensor unit. Thermocouples or other standard temperature sensors are used for the heat transfer measurements. A microcomputer samples the pressure and temperature data. As the only moving part is the membrane, with a maximum displacement of 5 micrometers, it is expected that the transducer system will be quite rugged and capable of withstanding large temperature variations as well as overloads up to twice its nominal range.

Keywords:
transducers guns high explosives ballistics high pressure high temperatur detonation wave propagatio

The development of an all optical pressure/temperature system is proposed to measuring rapid transients to 700 mpa/3000 deg k, as well as heat transfer, in gun interiors. Inherently, optical sensing not only has superb frequency response, spatial resolution and sensitivity, but also requires a simple sensor configuration. It enables the isolation of the detector through optical linking from the hostile environment, thereby minimizing instrumentation noise and drift. For pressure measurements, an optical pressure transducer (opt), which measures the deflection of a diaphragm via a fiber optic link, will be developed. To extend the temperature range into low values, miniature semiconductor near-ir lasers will be incorporated into the opt as the light source; this will also greatly enhance system portability. For temperature and heat transfer measurements, a combined version of an emission gauge and blackbody optical fiber thermometers will be developed. This combination will greatly improve the measurement accuracy achievable by using either type of sensor alone. Integration of these two types of sensors may be accomplished by sharing the same two-color pyrometric processor. All sensig elements will be made of refractory materials that can withstand flash temperatures typical of gun-barrel and/or explosive environments. The opt will be housed in a pcb 118 sensor body for immediate adaptation to existing ballistic facilities at ardec and other laboratories. The prototype system, controlled by a microcomputer, will first be tested in an upgraded high-pressure test facility originally designed and assembled in phase i, then it will be demonstrated on-site at ardec.

Keywords:
TRANSDUCERS GUNS HIGH EXPLOSIVES BALLISTICS HIGH PRESSURE HIGH TEMPERATUR DETONATION WAVE PROPAGATIO