基于声强技术的发动机噪声研究与控制--毕业论文.doc

天津职业技术师范大学 Tianjin University of Technology and Education 毕 业 设 计 专 业：汽车维修工程教育 班级学号： 汽修0712——18 学生姓名： 指导教师： 教授 天津职业技术师范大学本科生毕业设计 基于声强技术的发动机研究与控制 English title 专业班级：汽修 学生姓名： 指导教师：教授 学 院：汽车与交通学院 摘 要 汽车的噪声包括发动机噪声、轮胎噪声和传动机构噪声等，发动机是车辆行驶噪声的一个最主要的噪声源，车辆行驶噪声限值标准的降低必然要求更安静的发动机。 声音的物理度量常用声压、声功率和声强表示。声压是标量，通过它难以找出噪声源的方向和位置；声功率的测量则需要在价格昂贵的消声室中进行； 而声强是矢量，它能反映声场中某点声能的大小及其流动方向。声强法测量近声场可以迅速得出发动机各部分辐射噪声的分布情况，并准确、快速地分析出主要噪声源。用声强法来定位噪声源，其结果比用声压法测量得到的数据更可靠 本文主要针对的是汽车发动机噪声的分析。首先根据运用3599声强探头组件对长城491QE型发动机进行发动机噪声源测试，而后将实验数据通过数据线连接至PULSE，通过PULSE软件读取声强云图及数据流。对实验所得数据流进行分析。通过分别对发动机前端，左侧、右侧以及上侧的分析得出实验结论。 关键词：噪声；声强；长城491QE型发动机；数据分析 ABSTRACT The noise of the car, engine noise tyres including noise and transmission noise engine vehicle traffic noise is one of the main noise source, vehicle noise limit standard reduce inevitable requirement of the engine more quiet. The sound of the physical measure sound pressure, commonly used sound power and strong said. The sound pressure is scalar, through it is difficult to find out the direction of the noise source and position; The sound power is measured in need expensive dead room; And sound intensity is vector, it can reflect the field a certain point the size of the sound energy flow direction and. Sound intensity method for measuring the sound field can quickly draw near engine parts and the distribution of the radiation noise, and accurate, fast, the paper analyses the main noise source. With the sound intensity method to locate the noise source, the result with the sound pressure measurement than the data from the more reliable This paper mainly aims at is the car engine noise analysis. First of all, according to use 3599 sound intensity probe component to the Great Wall 491 QE type engine for engine noise test, and then will experiment data through the data connection to PULSE, through the PULSE software read sound intensity and data flow cloud. Of the experimental da