Exhaust Gas Temperature Sensing Using Thermally Luminescent Compounds

Jet engines operate at ever higher temperatures to achieve improved efficiency and performance, but the techniques for measuring the exhaust gas temperature (EGT), a critical parameter for evaluating the engine’s performance and maximizing lifetime, have not kept pace. Thermocouples rated at a high enough temperature have very weak signals (which can be drowned out by electromagnetic interference) or can’t be exposed to oxidizing environments. Other high temperature sensing techniques are not rugged enough, too expensive, or too complicated. TDA has developed a high temperature fiber optic thermometer that can reliably measure temperature from 300oC – 1800oC, more than hot enough for EGT sensing. TDA’s technology is insensitive to electromagnetic interference, oxidizing environments, or corrosive environments. The Phase I goal was proving that our new fiber optic temperature sensing concept could reliably measure temperature up to 1600oC. We achieved this goal by demonstrating that our proof-of-concept prototype could measure temperature from 300oC – 1800oC. In Phase II, we will develop an improved prototype (far more rugged than the Phase I prototype); we will radically reduce the price by replacing expensive laboratory equipment (needed in Phase I to better understand the sensing mechanism) with low cost off the shelf components.