Vibration and noise reduction of phononic crystal structure laid on the noise transmission path of axial piston pump

The radiated noise of an axial piston pump has been reduced previously by modifying shell structure. However, the effects of these methods of reducing vibration and noise are not clear. In this study, a noise reduction method that uses a phononic crystal structure on the vibration noise transmission path of a piston pump was developed. First, It was determined that the radiated noise frequency of the piston pump was the maximum peak frequency of the excavator field sound pressure level. A phononic crystal cell structure was designed based on the main noise peak frequency range of the axial piston pump. Comparing the vibration characteristics of the piston pump with and without the phononic crystal revealed that the vibration frequency of the piston pump can be significantly attenuated in the range of 409–1181.7 Hz. Finally, The average total sound pressure level of the external-field radiated noise of the axial piston pump was calculated based on the laid and non-laid phononic crystal structures. The results show that the average total sound pressure level amplitude decreases by 8.3 dB(A) in the frequency range of 0–1500 Hz. This study provides theoretical guidance for the design of an axial piston pump with low vibration and noise.