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汽车四大噪音来源分析 降噪需对症下药

在平时生活中,由于车噪、胎噪、路噪等各种声音交杂在一起,使得汽车在行驶时,车内并不安静,出现让人烦躁的噪音。然而,也有车友对汽车升级隔音之后的效果提出质疑,认为汽车升级隔音之后所屏蔽噪音的效果甚微甚至没效果,也增加了车辆的负重、油耗,这主要是车友选择的隔音产品的品牌和品质不当所致。汽车隔音应该怎么做呢?

 

汽车“全身”都是噪音源

汽车的噪音到底来源于哪里呢?有针对性地找出车上不同的噪音来源,才能对症下药,治“噪音”。北京赛车开奖记录美容专家介绍,汽车噪音有四个“源头”:发动机噪音、轮胎噪音、空气中的噪音和车身结构造成的噪音。

1.发动机噪音。

除发动机体发出的机械声外,还包括进气系统噪音,即高速气体经空气滤清器、进气管、气门进入气缸,在流动过程中,会产生一种很强的气动噪音。发动机噪音主要由挡火墙和驾驶室的前底板部位传入驾驶舱。

2.轮胎噪音。

一般的胎噪主要由三部分组成:一是轮胎花纹间隙的空气流动和轮胎四周空气扰动构成的空气噪音;二是胎体和花纹部分震动引起的轮胎震动噪音;三是路面不平造成的路面噪音。

3.空气噪音。

一是风噪,就是由车身周围气流分离导致压力变化而产生的噪音;二是风漏,或叫吸出音,是由驾驶室及车身缝隙吸气而与车身周围气流相互作用而产生的噪音;三是其他噪音,包括空腔共鸣等。

4.车身结构噪音。

主要是受两个方面因素影响,一是车身结构的震动传递方式,二是车身上的金属构件由于在里外作用下产生震动而产生噪音。

汽车隔音一般适合配置较低、舒适性较为一般的或更低端的小车。如果是高档车,原本的隔音已经相当好,再去花钱做隔音反而多此一举。

 

降噪手术

车主感觉在高速行驶时发动机声音太大,车外的声音能清晰听见,当时速高于80km时,轮胎发出的声音格外明显。根据车主的反映,师傅在进行了路试和全车检测后,发现这辆车的噪音来源主要来源于四个方面。

首先是发动机自身噪音。

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由于汽车公司在车辆设计时由于成本的问题,部分零件不会采用最好的材料,如该车引擎盖没有使用吸音材料,防火墙没有贴反音材料造成了发动机的声音通过仪表台下方、底盘传入到车内。

其次,车门噪音传导及车身密封性不足。汽车四个门是离车内最近结构,车门是由钣金件和门饰板组成。师傅特别指出,市场上售价在30万以下的新车,大部分车门部分都没有做隔音处理,因此在关门的时候可以感觉到明显的金属声音。

第三,轮胎产生噪音,叶子板、底盘传导噪音。轮胎产生的噪音首先跟轮胎的材质有直接关系,但主要原因还是在于这辆车车身,当轮胎产生噪音时,声音就会通过叶子板跟底盘传入车内。

第四,金属件传导是这辆车的噪音传递的重要途径。一般来说,低端车、高端车部分部件都是金属直接形成,未有任何的降音措施。在隔音施工时必须特别注意。



关于北京赛车开奖记录

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