Two-Dimensional Modeling of Skewed Dual Light Probe Signals for Blade Tip Clearance Measurement in Aeroengines

Accurate measurement of rotor blade tip clearance (BTC) is critical for aeroengine performance and safety. This paper presents two-dimensional models for predicting signals from a skewed-dual-light-probe (SDLP) used in laser triangulation-based Blade Tip Timing (BTT) systems. The models, based on total specular and diffuse reflection assumptions, simulate pulse signals generated in dual channels as a blade traverses the SDLP. A virtual SDLP is calibrated, and an experimental setup simulating blade translation validates the models. Results demonstrate that both models yield linear calibration curves for BTC measurement, with the diffuse reflection model showing closer alignment to experimental data. These models provide valuable insights for SDLP design, blade tip geometry, and sensor placement, offering significant potential for enhancing BTC measurement accuracy in aeroengine applications.