发动机振动引起的车内噪声控制研究

系统研究了某桥车发动机振动引起的车内噪声控制问题。通过试验分析，确定发动机二阶振动是引起车内噪声的主要原因，识别出发动机固体振动向车内传递的传递途径，并且确定对车内噪声有较大贡献的车身板件。在此基础上，通过对发动机、副下架橡胶支承元件弹性特性的修改，控制发动机振动向车内的传递，通过对车身顶棚结构板件的动力修改控制车身板件的振动。经样车试验得到满意的结果，证明了上述研究是十分成功的。

Research on Control of Car Interior Noise due to Engine Vibration

This paper presents a systematic and practical research on the interior noise control on a front wheel drive car equipped with a four cylinder in line engine. The result shows that the major factor governing the internal acoustic noise is the second harmonic of the engine vibration, which is transmitted to the car body through its power plant mount system, and that most of the noise is attributed to the vibration of its roof panel. Based on the analysis, two practical structure modifications are made: the modification of the stiffness of engine supporters to isolate the transmission of the engine vibration to the body, and the modification of the structure of the roof panel to reduce its response to engine vibration. As a result of the modifications, the interior noise level is reduced approximately by 1.5dB(A) and the interior noise environment is effectively improved.