关键词: 柴油发动机；噪音；减震螺栓；CAE 仿真分析

Abstract: Aiming at the vibration and noise issues of a diesel engine cover, an improved design scheme for damping bolts is proposed, intended to reduce mechanical vibration transmission through structural optimization and enhance noise, vibration, harshness (NVH) performance. A collaborative design process employing multiple methods is adopted. First, structural innovation design is carried out based on customer requirements, and key parameters are determined through theoretical mechanical calculations. Second, computer-aided engineering (CAE) simulation analysis is conducted to verify the structural design and evaluate leakage risks. Finally, prototypes are manufactured and bench tests are performed to validate the vibration and noise reduction effect of the newly designed damping bolts. Experimental data show that the optimized damping bolts achieve a reduction of 2 dB in the peak frequency-domain noise. The design scheme has passed fatigue life tests, meeting the 240 h durability test requirement. This research forms a complete design methodology from theoretical calculation to experimental verification, providing a standardized process for the development of engine damping components and demonstrating significant engineering application value.

Key words: diesel engine; noise; shock-absorbing bolt; CAE simulation analysis