Embedded Sensing for Gas Turbine Engine Component Health Monitoring

Abstract

Current rotorcraft gas turbine engines typically use titanium alloys and steel for compressor section and single-crystal nickel superalloys for the hot-section turbine stator vanes and rotor blades. However, these material selections are rapidly changing due to increased requirements on power-density and efficiency. Future Army gas turbine engines will be using ceramic matrix composites for many high temperature engine components due to their low density and improved durability in high temperature environment. The gas turbine industry is also actively developing adaptive concept technologies for production and assembly of modular gas turbine engine components with integrated sensing. In order to actively monitor engine components for extended seamless operation and improved reliability, it is essential to have intelligent embedded sensing to monitor the health of critical components in engines. Under this U.S. Army Foreign Technology Assessment Support (FTAS) program funded research project, surface bonded and embedded sensor patches from a U.K.-based company, Epsilon Optics Ltd., were experimentally evaluated to measure temperature responses on typical propulsion component material coupons. The temperature responses from this foreign technology sensor were assessed using a thermomechanical fatigue tester with a built-in furnace to conduct thermal cycling durability experiments. The experimental results obtained from the durability performance of this fiber-optic based embedded sensor are reported in this paper. This sensor technology upon maturation to higher TRL (Technology Readiness Level) levels can greatly reduce the lifecycle cost of future Army gas turbine engines.