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A Multi-Index Fusion Adaptive Cavitation Feature Extraction for Hydraulic Turbine Cavitation Detection
Yi Wang1, Feng Li1, Mengge Lv1
1Logistics Engineering College, Shanghai Maritime University, Shanghai 201306, China.
Entropy (Basel, Switzerland)
|April 26, 2025
Summary
Detecting cavitation in hydraulic turbines is crucial for efficiency and longevity. A new adaptive method improves cavitation feature extraction, leading to highly accurate detection with fewer false alarms.
Area of Science:
- Mechanical Engineering
- Fluid Dynamics
- Signal Processing
Background:
- Cavitation in hydraulic turbines causes mechanical damage, reducing efficiency and lifespan.
- Accurate cavitation detection is vital for operational reliability and performance.
- Extracting cavitation features is difficult due to noise and signal complexity.
Purpose of the Study:
- To propose a novel method for adaptive cavitation feature extraction and detection.
- To overcome challenges posed by noise and signal non-stationarity in hydroacoustic signals.
- To enhance the accuracy and reliability of cavitation monitoring in hydraulic turbines.
Main Methods:
- A multi-index fusion adaptive variational mode decomposition (VMD) algorithm was developed.
- The number of VMD decomposition layers was adaptively determined using cavitation indicators.
- Cavitation features were selected based on frequency characteristics for different cavitation degrees.
Main Results:
- The proposed method effectively retains cavitation information and improves feature extraction quality.
- Incipient and supercavitation were successfully detected.
- Experimental validation demonstrated high detection accuracy and a low false alarm rate.
Conclusions:
- The multi-index fusion adaptive method offers a robust solution for cavitation detection in hydraulic turbines.
- This approach enhances operational reliability and maintains energy conversion efficiency.
- The findings are significant for predictive maintenance and performance optimization of hydraulic machinery.
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