On-line real-time mistuning identification and model calibration method for rotating blisks based on blade tip timing (BTT)

Abstract

Identifying the mistuning parameters and calibrating the finite element model (FEM) of the mistuned blisk in real-time is a meaningful way to acquire the blisk’s dynamic characteristics and predict its stress response. Because of the wearing and other reasons, the blisk’s mistuning is changing during the operation. Hence a BTT based rotating-blisk mistuning identification and model calibration (BR-IDC) method in real-time has become a necessity. The rotating effects (stiffening, softening and Coriolis force) are considered in the BR-IDC. The synergistic effect of the mass and stiffness mistuning is analyzed, and the effect is presented by a standard mistuning coefficient. Based on the BR-IDC, the on-line real-time mistuning identification for the rotating blisk is realized. Furthermore, the FEM was calibrated by the identification results. The BR-IDC approach is verified by FEM simulation and experimental work. The precision of the FEM is improved through the calibration.