某单缸柴油机表面辐射噪声源试验分析与改进  

Test Analysis and Improvement on Surface Radiation Noise Source Identification for Single Cylinder Diesel Engine

作　　者：孟浩东[1] 李舜酩[1] 白莹[2] 徐毅 孙建中 饶海生 

机构地区：[1]南京航空航天大学能源与动力学院,南京210016 [2]常州信息职业技术学院图书馆,常州213000 [3]常柴股份有限公司,常州213002

出　　处：《南京航空航天大学学报》2012年第6期898-903,共6页Journal of Nanjing University of Aeronautics & Astronautics

基　　金：国家高技术研究发展计划("八六三"计划)(2009AA045102)资助项目

摘　　要：针对某单缸柴油机表面辐射噪声过大,整机声功率级超标的问题,采用9点声功率法与近场声压扫描阵面法相结合的识别方法,进行了柴油机主要表面辐射噪声源识别的试验分析,发现齿轮室盖、油底壳、水油箱是单缸柴油机主要表面噪声源的主要辐射部件。通过采用频谱分析方法,进一步研究了主要辐射部件振动特性与表面噪声辐射特性之间的关系。在此基础上,设计了一种具有高插入损失的紧贴式齿轮室盖隔声结构、选择了具有高阻尼特性的复合阻尼钢板油底壳、选取了新型尼龙合金复合材料制造的水油箱来降低单缸柴油机的表面辐射噪声。综合以上各种降噪方法,使得单缸柴油机整机噪声水平降低了1.5dB(A),优于国家标准要求。Aiming at the strong surface radiated noise occurred in single cylinder diesel engine which makes its sound power level higher than the national standard, the key surface radiation noise sources in diesel engine are identified by combing nine point sound power law and near field scan technique. Experi- mental analysis shows that the r^ain sources of surface radiation noise are gear housing cover, oil pan, and water and oil tank. By the use of frequency spectrum analysis method, the relationship between the vibration characteristics and surface radiated characteristics of the main noise components is studied. In order to reduce the surface radiated noise of single cylinder diesel engine, a kind of sound insulation close structure for gear housing cover which has high insert loss is designed, the composite vibration damping oil pan which has high damping capacity is selected, and water and oil tank made of the new complicated materials of nylon alloy are chosen. Sound power level of single cylinder diesel engine is reduced by 1.5 dB（A） with combining all the above methods for noise reduction, which makes it prior to the national standard.

关 键 词：单缸柴油机 声压扫描 噪声源 振动特性 隔声结构 复合阻尼 

分 类 号：TK421[动力工程及工程热物理—动力机械及工程]