Abstract: The exhaust manifold plays a crucial role in the engine exhaust system. The structural design of the exhaust manifold will affect the exhaust efficiency and service life of the engine. Different structural arrangements and manifold length designs have different impacts on exhaust performance. This article mainly focuses on the structural design of the engine exhaust manifold, and modal analysis is conducted on the designed exhaust manifold. After analysis, it can be concluded that the exhaust manifold is not affected by engine vibration resonance occurs due to factors such as vibration caused by uneven road surfaces, which improves the service life of exhaust manifolds and provides a reference for simulation analysis and research of exhaust manifolds.

Key words: Exhaust manifold; ANSYS; Engine; Modal analysis

摘要： 排气歧管在发动机排气系统中起着至关重要的作用，排气歧管结构设计将影响发动机 的排气效率和使用寿命，不同结构布置形式和歧管长度设计对排气性能有着不同的影响。文 章主要对发动机排气歧管进行结构设计及模态分析，经过分析可以得出排气歧管并没有因发 动机振动、路面不平引起振动等因素而发生共振。该设计可提高排气歧管使用寿命，同时为 排气歧管仿真分析研究提供了参考。

关键词: 排气歧管；ANSYS；发动机；模态分析