High Temperature Blade Health Measurement System using FOCIS

ABSTRACT: Modern turbine engines are advancing with remarkable progress in the development of increasing power, decreasing fuel consumption, and enhanced controls allowing for prognostic estimation of health. Even so, there are areas of these engines which can be dramatically improved given suitable enabling technology. One such area is in the adaptive adjustment of blade clearances, which can allow for higher fuel efficiencies and higher thrust to weight ratios. An additional area in which engines can be dramatically improved is in adopting a condition based approach to maintenance. Prime Photonics, LC (PPLC) will leverage its Fiber Optic Clearance and Identification Sensor (FOCIS) technology to develop a high-temperature, multi-function sensor platform to enhance the instrumentation capabilities for high performance turbine engines. The proposed sensor system will provide real time measurements of blade tip clearance, time of arrival, blade speed, and detection of foreign object damage, is intended for operation at temperatures of up to 1450 degrees C (2650 degrees F), and will be robust enough for flight engines. This effort extends prior work demonstrating the detection and identification of foreign object damage (FOD). This temperature range will be extended through the use of high temperature materials in the probe head, including sapphire, superalloys, alumina, and zirconia. BENEFIT: Using the high temperature PPLC FOCIS technology will allow for turbine engines which have greater performance, lower cost of manufacture, reduced fuel consumption, and lower maintenance costs. Through providing a single sensor which is capable of measuring all the parameters which the FOCIS system can, engines can reduce their instrumentation load, while increasing the value of the data obtained. Even so, there are areas of these engines which can be dramatically improved given suitable enabling technology. One such area is in the adaptive adjustment of blade clearances, which can allow for higher fuel efficiencies and higher thrust to weight ratios. An additional area in which engines can be dramatically improved is in adopting a condition based approach to maintenance, which allows for vast reductions in the cost of ownership of an engine over its lifetime. Both of these enhancements require the application of sensor technology which does not exist. The realization of these potential enhancements requires a robust, high-temperature, high-speed, multi-functional sensor system.