Optical semiconductor blade vibration monitoring system for gas turbine engine

A low-cost optical blade vibration monitoring system was designed to measure the deflection of vibrating gas turbine rotor blade tips under engine running conditions. The basic principle of the new system is the use of low-cost semiconductors and shorter optical fiber bundles. This approach yields a simple and inexpensive system with much less hardware than required for former systems. The results of basic tests show that the new semiconductor system performs at the same level of accuracy and a better S/N level. The system has been applied on development engines to monitor fan blade, compressor blade, and also turbine blade vibration and proved its capability. The system is about one third cost of the former system and has better performance