Identification method of rotor blade axial displacement based on blade tip timing

Blade tip timing technology has improved in recent years and is now frequently utilized in the monitoring and diagnosis of turbomachinery blade vibration. It is necessary to decouple the measurement results of blade tip timing and determine the axial displacement of the blade, because the measurement results of the blade tip-timing method are the components of the blade tip displacement in the rotational direction, and the change in the position of the measurement points for blade tip timing caused by the axial displacement of the blade also introduces the displacement components in the rotational direction. A blade axial displacement identification method based on the principle of blade tip timing measurement is proposed after analyzing the link between the change in measurement point position and the measurement result. Integrating the blade profile equation, a sample model of blade tip timing that incorporates blade axial displacement is established, and the efficiency of the proposed method is verified by simulation. The measured blade tip timing signals from the adjustable axial displacement aero-engine compressor blade are then used for experimental verification, and the axial displacement identification values of the rotor blade are compared with the actual values, verifying the accuracy of the proposed method. It has significant engineering application value for thoroughly and accurately assessing blade operation status and diagnosing rotor-blade axial displacement faults.