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

摘要： 针对柴油发动机罩盖振动噪音问题，提出一种改进减震螺栓设计方案，旨在通过结构 优化降低机械振动传递，提升噪声、振动与声振粗糙度（NVH）性能。采用多种方法协同设 计流程，首先基于客户需求进行结构创新设计，通过理论力学计算确定关键参数；其次运用 计算机辅助工程（CAE）仿真分析验证结构设计，评估泄漏风险；最后制作样品开展台架实 验，验证新设计减震螺栓的振动噪音改善效果。实验数据表明，优化后的减震螺栓可使，频 域噪声峰值减少 2 dB。设计方案通过疲劳试验验证，满足 240 h 耐久试验要求。该研究形成 了一套从理论计算到实验验证的完整设计方法，为发动机减震部件开发提供了标准化流程， 具有工程应用价值。

关键词: 柴油发动机；噪音；减震螺栓；CAE 仿真分析