Blade Vibration Difference-Based Circumferential Fourier Fitting Algorithm for Synchronous Vibration Parameter...

Area of Science:

• Mechanical Engineering
• Vibrational Analysis
• Rotating Machinery

Background:

• Blade vibration is critical for the efficiency and safety of rotating machinery.
• Blade tip timing (BTT) is a key technique for monitoring blade vibration.
• Existing BTT methods suffer inaccuracies due to non-stationary factors in real-world applications.

Purpose of the Study:

• To develop a high-precision BTT technique for blade vibration monitoring.
• To address the inaccuracies in traditional BTT methods.
• To propose an optimized algorithm for blade synchronous vibration parameter identification.

Main Methods:

• Optimization of the traditional circumferential Fourier fitting (CFF) algorithm.
• Acquisition of four sets of BTT signals using two probes based on blade departure time.
• Establishment of six sets of blade vibration differences.
• Proposal of a blade vibration difference-based circumferential Fourier fitting (BVD-CFF) algorithm.

Main Results:

• The BVD-CFF algorithm demonstrates superior anti-noise performance in simulations.
• Experimental validation on high-speed rotation and large-scale centrifugal compressor test rigs.
• Identified engine orders of blade synchronous vibrations closely match strain gauge method results.

Conclusions:

• The BVD-CFF algorithm offers a robust and accurate solution for blade vibration monitoring.
• This method improves the precision of BTT techniques in practical engineering scenarios.
• The findings support the application of the BVD-CFF algorithm in assessing the health of rotating machinery.