Innovative TBC Blade Imaging System for Surface Temperature Mapping

Sensors are vital during advanced turbine engine development testing. Essential data expedite engine development programs and accordingly bring new advanced propulsion and ground-power engines to market sooner. Ceramic thermal barrier coating (TBC) on first-stage turbine blades is now a vital component of advanced engines under development for future military aircraft, protecting the metal alloy blades from the extreme combustion temperature in these high-performance engines. TBC must be proven as a reliable means to prevent blade failure, but current engine development programs are mired since there is not a sensor available to map the surface temperature of TBC blades during engine operation. In fact, the engine sensor community has identified surface temperature mapping of TBC blades as the highest priority sensor development need. Phase I of this project demonstrated the feasibility of an optical sensor to provide TBC surface temperature mapping. Designed within the dimensional constraints of a current on-engine optical probe, the sensor was characterized for spatial resolution exceeding conventional heat flux gauge resolution of 0.125 inches. Whole-blade temperature measurements taken on the torch-heated blade were significant for demonstrating the thermal-mapping capability and for distinguishing TBC defects. Phase II will proceed with implementation of strategic optical and imaging hardware improvements identified for Phase II development. The high performance system is expected to achieve even better spatial resolution, and in a one microsecond sampling period which is necessary to capture images of high-speed TBC turbine blades. On-engine demonstrations will be performed.