关键词: 发动机噪声；噪声分类；燃烧噪声；机械噪声；空气动力噪声

Abstract: This paper analyzes the mechanism, noise classification and manifestation of engine noise. Divide the factors that affect the noise into combustion noise, mechanical noise, and aerodynamic noise, and elaborate on their mechanism and control measures. The optimization of reducing combustion noise can be achieved through methods such as combustion chamber optimization, airway optimization, and combustion parameter optimization. Reducing mechanical noise can be achieved by optimizing the clearance between the piston and cylinder, optimizing the valve train, and optimizing gear transmission. Reducing aerodynamic noise can be optimized from the source and transmission path directions.

Key words: Engine noise; Noise classification; Combustion noise; Mechanical noise; Aerodynamic noise