曲轴扭转振动导致的内燃机噪声

Engine noise resulting from crankshaft torsional vibrations

为了进一步探讨内燃机噪声与曲轴扭转振动的关系，在对活塞、曲柄、连杆机构的动力学分析和试验研究的基础上，探讨了曲轴扭转振动共振时，将导致部件的相互作用加剧，增大结构的噪声；还指出，当曲轴有扭转共振时，扭振减振器可有效地降低噪声；通过对发动机机体的动态设计，使机体有合理的振型和固有频率，以及优化活塞与缸套的配合是降低曲轴振动与机体辐射噪声的重要措施．

In order to reveal the relations between engine noise and crankshaft torsional vibration, the dynamics of the piston con rod crank train is analyzed, and theoretical analysis is proved through experiments. The results show that torsional dampers can effectively reduce the noise excited by the torsional resonance, and it is necessary to make sure that the vibration mode and the natural frequencies of the engine block, the piston profile and the clearance between piston and cylinder should be optimized.