Hybrid wireless-wired optical sensor for extreme temperature measurement in next generation energy efficient gas turbines

Accuracy, reliability, and long lifetimes are critical parameters for sensors measuring temperature in gas turbines of clean coal-fired power plants. Greener high efficiency next generation power plants need gas turbines operating at extremely high temperatures of 1500°C, where present thermocouple temperature probe technology fails to operate with reliable and accurate readings over long lifetimes. To solve this pressing problem, we have proposed the concept of a new hybrid class of all-silicon carbide (SiC) optical sensor, where a single crystal SiC optical chip is embedded in a sintered SiC tube assembly, forming a coefficient of thermal expansion (CTE) matched all-SiC front-end probe. Because chip and host material are CTE matched, optimal handling of extreme thermal ramps and temperatures is possible. In this article, we demonstrate the first successful industrial combustor rig test of this hybrid all-SiC temperature sensor frontend probe indicating demonstrated probe structural robustness to 1600°C and rig test data to ~1200°C. The design of the rig test sensor system is presented and data are analyzed.