A Review of Fiber Optic Technology for Turbine Engine Instrumentation Channel: Control, PHM, and Test Cell Applications

The next generation of gas turbine engines will potentially have Full Authority Digital Eengine Control (FADEC) Systems that consists of wired, wireless, and fiber optics technologies. This paper focuses on the fiber optics technologies for engine applications. Optical fiber sensors have the potential to deliver new and effective measurement in many applications aided by the following properties: (a) immunity to and non-generation of electromagnetic interference (EMI), (b) electrical passivity and thus safety in explosive environments, (c) transmission of sensed information over long distances and through difficult to access regions, (d) very small diameter size allowing integration into smart materials, (d) high durability in many environments, (e) minimal mass, particularly important in aerospace applications, (f) geometric flexibility coupled with capability for multiple functionality, enabling non-line-of-sight measurements and contributing to ease of installation compared with alternative approaches. For practical application a fiber optic sensing system needs to include: sensors, fiber optic link, interrogator (comprising photonics, electronics and firmware/software), data interpretation and decision-aid algorithms/software. Fiber optics for diagnostics and troubleshooting are used in varying capacities to test, measure, analyze, transmit, distribute, and/or simulate an optical signal with which procedures and processes associated with maintenance, problem solving, and calibration of equipment and/or networks can be performed. With all the scientific and engineering advancements in the field of fiber optic sensing, the maturity of this technology is high enough and well beyond the experimental lab environment. With its rather low cost, fiber optics sensing technology is a proper option for turbine engine industry.