The Piston Slap Force Reconstruction of Diesel Engine Using WOA-VMD and Deconvolution
Shigong Fan1, Yixi Cai1, Yunxi Shi1
1School of Automotive and Traffic Engineering, Jiangsu University, Zhenjiang 212013, China.
Sensors (Basel, Switzerland)
|June 27, 2024
Summary
This study presents a novel method to accurately determine piston slap force in diesel engines. The technique uses optimized variational modal decomposition and deconvolution to analyze vibration data, aiding engine design.
Area of Science:
- Mechanical Engineering
- Automotive Engineering
- Vibration Analysis
Background:
- Piston slap is a primary excitation source in diesel engines, occurring with fuel combustion.
- Measuring combustion pressure is feasible, but quantifying piston slap force is challenging without direct testing.
- Traditional Variational Modal Decomposition (VMD) methods are susceptible to noise, impacting parameter accuracy and slap response extraction.
Purpose of the Study:
- To develop and validate a robust method for identifying piston slap force in diesel engines.
- To overcome the limitations of traditional VMD in noise interference and improve slap force calculation accuracy.
- To provide insights into piston vibration characteristics for optimized engine structural design.
Main Methods:
- Obtained the transfer function between excitation and vibration response via percussion tests.
- Employed an optimized Variational Modal Decomposition (VMD) method, utilizing a whale algorithm, to isolate slap response from block surface acceleration.
- Applied deconvolution, enhanced with singular value decomposition and regularization, to calculate the slap force and mitigate ill-conditioning.
Main Results:
- Successfully separated the piston slap response from engine block surface acceleration using the optimized VMD.
- Calculated the piston slap force with improved accuracy by employing deconvolution with singular value decomposition and regularization.
- The developed method effectively addresses the ill-conditioning issues common in deconvolution inverse problems.
Conclusions:
- The proposed method offers a viable approach for accurately evaluating piston slap force in diesel engines.
- This technique enables detailed analysis of slap force's angular distribution and shock positions on the piston liner.
- The findings facilitate a better understanding of piston vibration characteristics, crucial for optimizing diesel engine structural design.
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