A spectrum reconstruction method for blade vibration measurement based on probe waveform analysis

Blade tip timing (BTT) is regarded as a promising noncontact measurement technology for rotating blade health monitoring. However, the number and layout of probes, required by BTT, hinder the application of BTT. To overcome these shortcomings, a probe waveform spectral reconstruction method (PWSR) is proposed, which combines the advantages of waveform analysis method and wideband signal interpolation method. PWSR can be summarized in two steps: obtaining more displacement information from the output waveform of probes and identifying vibration parameters of blades. Simulations are conducted to investigate the effectiveness of PWSR for single-harmonic and multi-harmonic blade vibration parameters identification. Its sensitivity and robustness are also studied. An experiment to validate the proposed method is performed on a rotating blade test bench, and compared with strain gauge test data. Experimental results show that the proposed method can identify the amplitude, frequency and phase of the blade vibration accurately via one probe.

Automated summary

Blade tip timing (BTT) is a promising noncontact measurement technology for rotating blade health monitoring. However, the limitations of the number and layout of probes required by BTT hinder its application. To overcome these drawbacks, a probe waveform spectral reconstruction method (PWSR) is proposed, combining the advantages of waveform analysis and wideband signal interpolation methods. PWSR accurately identifies blade vibration parameters, proving its effectiveness and robustness through simulations and experiments.