Review of Non-Contacting Displacement Measurement Techniques Used to Monitor the Movement of Rotor Blades in Gas Turbine AERO Engines

摘要

Techniques to measure the changes in rotor blade geometry which occur during a flight cycle are discussed. They include measurement of blade tip axial position by optical or inductive techniques; measurement of blade tip clearance by optical or capacitive techniques; and measurement of blade untwist and decamber using timing probes. All the techniques involve the use of relatively easily installed casing mounted sensors to monitor the tips of the rotor blades. They can all normally be fitted to standard engine parts using modifications which require only the removal of metal.