In-situ dynamic measuring system to measure the vibratory and translational displacement of the airfoil modes of a combustion turbine compressor vane via an optical non-contact method

摘要

An in-situ Dynamic Measuring System is developed and tested to measure the vibratory and translational displacement of the airfoil modes of a combustion turbine compressor vane via an optical non-contact method. The Dynamic Measurement System measures the dynamic contact displacement in the radial direction of the combustion turbine, which can be implemented as measurement of radial displacement on the axial contact surface. The dynamic system is a noncontact device that uses a fiber optic bundle for the sensor element probe. The probe's fibers are connected to a module which in turn plugs into the display controller. The probe is placed in proximity of the target area. Motion of the target is determined by the amount of light received by the probe. The fiber bundle system is capable of simultaneous measurement of vibratory (AC) motion and free body or translational (DC) motion. The AC modes are resolved spectrally by an FFT of the raw fiber optic bundle signal. The fiber optic bundle correctly identified the modes and their associated magnitude on the airfoil and measured the displacement of the target area.