Gasoline Engine 161CC Mechanical Noise Analysis And Reduction Study

Due to the more stringent legislations of circumstance noise and emission as well as the increasing expectation by the consumers, researches on the noise, engine noise have become more important in recent years. Noise index is an important aspect in evaluating engine's performance. So it's important to analysis and control the engine noise today.Engine noise is the main noise source of automobile, motorcycle, general purpose engine to the internal combustion engine as power, so the control technology of internal combustion engine noise has become a common concern of the industry in question. Noise of internal combustion engine in the work can be divided into the intake noise, exhaust noise, motion work of mechanical noise and combustion noise according to the noise source. The mechanical noise as the main component of internal combustion engine noise, control of the mechanical noise of internal combustion engine can effectively reduce the noise of internal combustion engine.In this paper, the research object is 161 CC gasoline engine,we use a way that combining experimental and theoretical analysis methods to study the piston knocking noise, valve operation noise and primary gear drive noise. And at the same time, according to the sound mechanism of mechanical noise and of gasoline engine and also combining the engine's structure characteristic. Optimizing the valve mechanism layout and cam profile,and the gap between piston and cylinder to improve the piston motion characteristic,change the material of the timing gear and the cam to reduce the noise.