Deformation Monitoring of High-Speed Rotors using a Non-Incremental Interferometric Measurement System

摘要

We present a non-incremental interferometric measurement system for in-process monitoring of the dynamic behaviour of high-speed rotors, which is essential for improving safety and energy efficiency of motors and turbo machines, such as aircraft engines. The measurement system is based on the novel laser Doppler distance sensor which exhibits the unique feature that its measurement uncertainty of some microns is independent of the velocity of the device under test. This allows precise measurements of rotor deformations and blade vibrations even at high rotor speed. By aligning three sensors equally spaced by angles of 120° along the circumference of the rotor, dynamic deformations such as radial expansion and tumbling motions of the rotor can be measured simultaneously. Due to the robust fiberoptic sensor design, measurements can be carried out under vacuum condition and at high temperatures too.