英文翻译
With the rapid development of automobile industry, there is comfort and vehicle vibration and noise control of more and more stringent requirements. According to relevant data shows that 70 percent of the city noise from the traffic noise, and traffic noise is mainly car noise. It is seriously polluting the urban environment, affecting people's life, work and health. So noise control is not only related to comfort, but also related to environmental protection. However, all also from the vibration noise, vibration can cause certain parts of the early fatigue damage, thereby reducing the service life of motor vehicles; excessive noise can damage hearing the driver will enable the rapid driver fatigue, thus driving security constitutes a grave threat. So noise control, is also related to motor vehicle durability and safety. Thus vibration, noise and comfort are the three closely related, it is necessary to reduce vibration, reduce noise, but also improve ride comfort, and ensure the product economy, vehicle noise control in the standard range.
One type of noise arising from car noise are the main factors of air power, mechanical drive, the electromagnetic three parts. From the structure can be divided into the engine (combustion noise), the chassis noise (power train noise, all components connected with the noise), electrical equipment, noise (cooling fan noise, car noise generator), body noise (such as body structure, shape and attachment installation unreasonable noise). One of the engine noise accounted for more than half of motor vehicle noise, including noise and body intake noise (such as engine vibration, the rotational axis Valve, Jin, door switches, such as exhaust noise). Therefore the engine vibration, noise reduction has become a key automotive noise control.
In addition, automobile tires at high speed, it will also cause more noise. This is because of the tire at the ground flows, the pattern is located in the air by ground tank and re-extrusion process caused by inhaling gas pump sound, as well as tread patterns with percussive sound of the road.
noise requirements of regulations in Europe, from October 1996 onwards, the external bus 77dBA noise must be reduced to 74dBA, noise was reduced by half energy, the end of the century further reduced to 71dBA. Japan's laws and regulations, small car in the next decade to control noise standards at the following 76dBA. A number of domestic cities are also planning to traffic trunk lines in 2010 to control noise at the average of less than 70dBA. According to the domestic current data indicate that the domestic value of bus noise permit shall not exceed 82dBA, light trucks for 83.5dBA. This shows that our country in the vehicle noise control will have to make do.
noise assessment noise evaluation mainly refers to the car, outside noise and vibration adaptive value. Evaluation methods can be divided into subjective evaluation and objective evaluation. Subjective assessment of the impact of vehicle noise is a major factor in comfort, loudness and uncertainties, such as semantic differential method can be used for subjective evaluation. At an objective evaluation, can be used PCNM noise measuring device for measuring test analysis; addition simulation technology in the finite element method (FEM) and boundary element method (BEM) has been widely applied.
noise control noise generation and dissemination in accordance with the mechanism of noise control technology can be put into the following three categories: First, the control of noise sources, are two routes of transmission of noise control, noise three recipients are protected. One of the control of noise sources are the most fundamental, the most direct measures, including noise reduction to reduce the exciting force and the engine parts of the exciting force response, which means transformation of acoustic source local oscillator. However, it is difficult to control noise sources when necessary in the route of transmission of noise to take measures, such as sound absorption, sound insulation, noise reduction, vibration and vibration isolation measures. Motor vehicles and vehicle vibration and noise reduction level of power, economy, reliability and strength, stiffness, quality, manufacturing costs and use are closely related.
engine to reduce vibration and noise of the engine noise is the focus
of automotive noise control. Engine vibration and noise are generated at source. Engine noise is from fuel combustion, valve bodies, gears and piston timing noise percussion synthesis.
(1) ontology engine noise
Lower engine noise will be ontological transformation of local oscillator sound sources, including methods such as finite element method analysis and design engines, selection of soft combustion process, improve the structure of the body stiffness, with the use of tight space, reduce noise cylinder cover. For example in the oil pan on an additional stiffener and diaphragm to improve the stiffness of oil pan to reduce vibration and noise. In addition, give the engine Tu damping material is an effective approach. Damping materials can kinetic energy into thermal energy. To deal with the principle of damping is a damping materials and components into its vibrational energy to consume. It has the following structure: Freedom damping layer structure, and spacing of freely damping layer structure, and constrained damping layer structure and spacing of constrained damping layer. It is clear that the adoption of a decrease of resonance amplitude and accelerated the decay of free vibration, reducing the various parts of the Chuan-Zhen capacity, an increase of parts at or above the critical frequency of vibration isolation capacity. At present, some countries have designed an engine experts active vibration isolation system to reduce engine vibration, in order to achieve the purpose of noise reduction.
(2) intake noise
Engine intake noise is one of the main noise source, the Department of the engine noise of air power, with the engine speed increases to strengthen. Non-supercharged engine intake noise major components, including the cyclical pressure fluctuation noise, vortex noise, the cylinder of the Helmholtz resonance noise. Diesel engine supercharger intake noise mainly from the turbocharger compressor. Two stroke engine noise from the Roots pump. In this regard, the most effective method is the use of intake muffler. There is a resistive type muffler (absorption type), resistant muffler (expansion type, resonance type, interference-type and porous decentralized) and the composite muffler.
To combine with the air filter (that is in the air filter on an additional resonance chamber and sound-absorbing material, for example, type R3238) has become the most effective intake muffler, muffler volume of more than 20dBA.
4.2 Chassis Noise
(1) Department of exhaust noise
Department of the chassis exhaust noise is the main noise sources, mainly from the exhaust pressure pulsation noise, air flow through the valve seat when issued by eddy current noise, because of boundary layer airflow disturbance caused by noise and exhaust Office jet noise composition.
Designed to optimize the performance of a good muffler, to reduce car noise are one of the important means. Optimize design method has acoustic finite element method and acoustic boundary element method, but is still in its infancy. Muffler to avoid the transmission characteristics and vibration characteristics of coupled mufflers are designed to be focused on solving a problem. Secondly, to reduce exhaust noise and improve power is also a pair of contradictions, because to reduce exhaust noise and lower exhaust back pressure on the design of the exhaust pipe has a diameter of conflicting demands, the former requires a smaller diameter, which is opposite . In this regard, the use of parallel flow path of the dual function muffler, at reduced air pressure and reduce noise to be effective. In addition, the engine exhaust manifold to the muffler inlet pipe section, the use of flexible pipe vibration, noise reduction effect can be reduced to about 7dBA.
(2) power train noise
Powertrain noise from the vibration caused by变速齿轮meshing and rotating shaft vibration. General measures taken are: First, choose low-noise transmission, engine and gearbox are two and the main reducer, such as rear axle and chassis components for flexible rubber pad connections, so as to achieve the purpose of isolation; are three-axis rotational control balance degrees, to reduce torsional vibration.
4.3 Electric equipment noise
(1) cooling fan noise
Cooling fan noise happened devices are subject to wind retaining ring, water pump, radiator and transmission, but the noise generated depends primarily on the chassis.
(2) automobile generator noise
Automotive generator noise depends on the effects of a variety of sources, these sources have magnet source, mechanical and air power source. Noise level depends on the generator magnetic structure and ventilation systems, as well as generators precision manufacturing and assembly.
4.4 Body Noise
As the speed increased, the body will be more and more noise, and air power are the main causes of noise. Therefore, the following programs to improve the body noise: First, to streamline the design of the body, achieve a smooth transition; two are in between the body and frame components to adopt a flexible connection; three interior is softened, such as Inner Mongolia at the roof and body skin the use of sound-absorbing material.
In addition, the car at high speed when the tire is also a source of noise. Real vehicle Inerting line method has been measured: Tire Tread greater, then the greater the noise. In addition, the tire tread with the noise generated also have a great relationship, there is a reasonable choice of the pattern of steel cord for radial tires to reduce tire noise are an effective way. Materials for the tire, the use of more flexible and soft rubber with high, you can create a low-noise tires.
4.5 Other measures
Automobile noise control, except in the design on the use of optimization methods and optimization of selected components, it can also carry out active control of noise. This is based on sound muffler technology, the principle is: the use of electronic muffler system with the opposite phase of the acoustic noise, vibration so that the two cancel each other out in order to reduce the noise. This muffler device used extremely advanced electronic components, has excellent noise reduction effect can be used to reduce vehicle noise, engine noise, the engine could also be used to proactively support systems, to offset the engine vibration and noise
随着汽车产业的快速发展，对车辆的舒适性、振动和噪声控制要求越来越严格。据有关资料表明，百分之七十的城市噪音来自交通产生的噪音，而交通噪音主要是汽车噪音。这对城市的环境污染非常严重，影响到人们的生活、工作和健康。。因此，控制汽车产生的噪声，不仅关系到舒适性，而且也与环境保护有关。另外，噪音来源于振动，而振动会导致汽车的某些部件过早的出现疲劳损伤，从而减少机动车的使用寿命; 过量噪音可损害司机的听力，司机在振动中非常容易迅速的疲劳驾驶，从而对安全构成严重的威胁。因此，噪声控制，也关系到汽车的耐用性和安全性。因此振动，噪声和舒适性是三个密切相关的因素，想要减少振动，降低噪音，提高乘坐舒适性并且确保汽车的经济性，车辆噪声必须控制在标准范围内。
由空气动力，机械传动，电磁三部分引起的噪音是汽车噪音的一种类型。从结构可分为发动机噪音（即燃烧噪声） ，底盘噪音（即传动系噪声，所有的组件噪声） ，电气设备噪音（冷却风扇噪声，汽车噪声发生器） ，机构噪音（如车身结构，形状和附件安装不合理的噪音） 。其中一个发动机噪声占了机动车一半以上的车辆噪声，包括发动机本身的噪声和车辆摄入噪声（如发动机振动，转动轴阀，进、排气门开关，如排气噪声等） 。因此，减少发动机振动，降低噪音已成为一个关键的汽车噪声控制。
此外，汽车轮胎在高速时，它也将带来更多的噪音。这是因为轮胎在地面流动的格局位于空中和地面之间，气流经过挤压被吸入轮胎，与轮胎花纹的撞击的声音。
在欧洲，对于汽车噪音有专门的法规要求，从1996年10月起，外部总噪音必须从77dBA 减少到74dBA ，噪音的减少了节约了一半的能源，在本世纪末进一步降低到71dBA 。日本也有相应的法律和规章，小型车在未来十年内，必须把噪音控制在76dBA 以下 。
国内的一些城市也计划在2010年交通干线上控制噪声平均值小于
70dBA 。根据国内目前的数据表明，国内驾驶巴士的噪音许可不得超过82dBA ，轻型卡车为83.5dBA 。这表明，我国在车辆噪声控制方面将越来越完善。
噪音的评估与噪音的评价主要是指车外噪音和振动自适应价值。评价方法可分为主观评价和客观评价。汽车噪音是一个影响舒适性的主要因素，对人体的感觉是不确定因素，主观评价于每个人来说是有差异的。而客观的评价则可以用PCNM 噪声测量装置测量测试分析; 此外仿真技术在有限元法（ FEM ）和边界元法（ BEM ）已得到广泛的应用。
控制噪音的产生和传播根据该机制的噪音控制技术，可以分为以下三类： 第一，控制噪声源，
第二，通过控制传播途径对噪声进行控制，
第三，对噪声的接受者即乘客和驾驶者进行保护。
而第一个控制噪声声源是最根本，最直接的措施，包括降低噪音，减少激振力和发动机部件对激振力的反应，这意味着转化声源本身的振荡。然而，这种噪声源是难以控制的，必要时对噪声的传播途径采取措施，例如利用吸声，隔声来减少噪音，采取振动和振动的隔离措施。车辆的振动和噪声对于机动车辆降低能耗水平，提高经济性、可靠性和强度、刚度、降低这两本身质量、制造成本和使用等密切相关。
控制汽车噪声的重点是减少发动机引擎的振动和噪音。引擎是发动机振动和噪声产生的源头。发动机噪声是由燃料燃烧，阀体，齿轮，活塞敲击缸体等噪音合成。
（ 1 ）发动机本体噪音
降低发动机噪音将本体论的转变，本地振荡器声源，方法包括：如有限元法分析和设计引擎，选择软燃烧过程，改善结构，提高材质的刚度，利用严格的空间安排减少间隙，降低气缸盖的噪声。例如在油底壳上额外加力和隔膜，可以改善油底壳刚度，以减少振动和噪声。此外，在发动机上涂阻尼材料也是一种有效的办法。阻尼材料能够把动能转化成热能。处理的方法是：一种阻尼减振材料，其部件吸收振动能量并转化成其他方式消耗掉。它具有以下结构：自由阻尼层结构，间隔自由阻尼层结构、约束阻尼层结构和间隔约束阻尼层。很显然，通过减少了共振振幅和加速衰变的自由振动，从而减少了各部分的传振能力，增加了部分达到或超过临界频率振动隔离能力。
目前，一些国家的专家设计的发动机主动隔振系统，以减少发动机振动，以实现降低噪音的目的。
（ 2 ）摄入噪音
发动机进气噪声是主要噪声源，该部份是发动机噪声的空军力量，随着发动机转速的增加而加强。非增压发动机进气噪音的主要组成部分，包括周期性压力脉动噪声，涡流噪声，汽缸的亥姆霍兹共振噪声。
柴油机增压器进气噪音主要来自涡轮增压压缩机。在这方面，最有效的方
法是使用多种消声器。有一个电阻型消声器（吸收型） ，抗性消声器（膨胀型，共振型，干涉型和多孔分散）和复合消声器。结合了空气过滤器（即在空气过滤器的额外共振和吸声材料，例如，输入R3238 ）已成为最有效的消除摄入噪音的消声器，通过消声器消音可超过20dBA 。
4.2底盘噪声
（ 1 ）底部排气噪声
底部的主要噪声源于底盘排气噪声，主要是来自排气压力脉动噪音，空气流经阀座时发出的涡流噪声，由边界层气流扰动所造成的噪音和排气管喷气噪声组成。
在其排气管道使用性能良好的消声器，是减少汽车噪音的重要手段之一。优化设计方法有声学有限元法和声学边界元法，但这两种方法仍处于初级阶段。以避免传播特性和振动特性的耦合消声器的目的是把重点放在解决问题。
首先，着眼于解决问题。
其次，降低排气噪声和改善电源也是一对矛盾，因为，以减少排气噪声和降低排气背压时设计的排气管的直径二者是相互冲突的两种要求，前者需要直径越小越好，这是一方面，在这方面，使用平行流路的双重职能消声器，以降低空气压力和降低噪声是有效的。此外，发动机的排气管消声器进入排气管，使用灵活的管道振动，降低噪声的影响可降低到大约7dBA 。
（ 2 ）动力总成噪声
造成动力总成的振动噪音是变速齿轮啮合和旋转轴振动。一般采取的措施是：第一，选择低噪音的传播途径，连接发动机的是变速箱和两个主要减速器，如后轴和底盘的部件用灵活的橡胶垫连接，从而实现分离的目的; 有三个轴转动的要控制平衡度，以减少扭振。
4.3电气设备噪声
（ 1 ）冷却风扇噪音
冷却风扇噪声发生设备受风护环，水泵，水箱和传输的影响，但所产生的噪音主要还是取决于底盘。
（ 2 ）汽车发电机噪声
汽车发电机噪声的影响取决于各种不同的来源，这些来源有磁铁源，机械
和空气动力源。噪音水平取决于发电机磁结构和通风系统，以及发电机，精密制造和装配。
4.4车身噪声
随着汽车速度的增加，车体将被越来越多的噪音所打扰，空气阻力是噪音的主要原因。因此，增加以下程序，以改善身体噪音：第一，精简机构的设计，实现平稳过渡; 身体和框架两者之间的的组成部分，采取一种灵活的连接; 三个内部进行软化，如内蒙古的屋顶和主体外面的材料使用吸声材料。
此外，赛车在高速时的轮胎也是一种噪音来源。实车惰化线法进行了测试：轮胎的横截面积越大，那么噪音就越大。此外，胎面的材料与所产生的噪音也有很大的关系，现在有一个合理的选择的模式就是用用钢丝帘线的子午线轮胎，以降低轮胎的噪声，这是降低噪声的一种非常有效途径。
这种材料的轮胎，使用更加灵活，软橡胶含量很高，以此可以创建一个低噪的音轮胎。
4.5其他措施
汽车噪声控制虽然不是很具有确定性，但在设计上使用最优化方法和优化的选定部分，它也可以进行主动控制噪音。这是基于良好的消声器技术，其原理是：利用电子消声系统与相对阶段的噪声，
两个能够相互抵消的振动，可以以减少噪音。这种消声器装置采用非常先进的电子元件，具有良好的降噪效果可用于减少汽车噪音，发动机噪音，发动机也可以用来积极支持系统，以抵消发动机的振动和噪声。
英文翻译
With the rapid development of automobile industry, there is comfort and vehicle vibration and noise control of more and more stringent requirements. According to relevant data shows that 70 percent of the city noise from the traffic noise, and traffic noise is mainly car noise. It is seriously polluting the urban environment, affecting people's life, work and health. So noise control is not only related to comfort, but also related to environmental protection. However, all also from the vibration noise, vibration can cause certain parts of the early fatigue damage, thereby reducing the service life of motor vehicles; excessive noise can damage hearing the driver will enable the rapid driver fatigue, thus driving security constitutes a grave threat. So noise control, is also related to motor vehicle durability and safety. Thus vibration, noise and comfort are the three closely related, it is necessary to reduce vibration, reduce noise, but also improve ride comfort, and ensure the product economy, vehicle noise control in the standard range.
One type of noise arising from car noise are the main factors of air power, mechanical drive, the electromagnetic three parts. From the structure can be divided into the engine (combustion noise), the chassis noise (power train noise, all components connected with the noise), electrical equipment, noise (cooling fan noise, car noise generator), body noise (such as body structure, shape and attachment installation unreasonable noise). One of the engine noise accounted for more than half of motor vehicle noise, including noise and body intake noise (such as engine vibration, the rotational axis Valve, Jin, door switches, such as exhaust noise). Therefore the engine vibration, noise reduction has become a key automotive noise control.
In addition, automobile tires at high speed, it will also cause more noise. This is because of the tire at the ground flows, the pattern is located in the air by ground tank and re-extrusion process caused by inhaling gas pump sound, as well as tread patterns with percussive sound of the road.
noise requirements of regulations in Europe, from October 1996 onwards, the external bus 77dBA noise must be reduced to 74dBA, noise was reduced by half energy, the end of the century further reduced to 71dBA. Japan's laws and regulations, small car in the next decade to control noise standards at the following 76dBA. A number of domestic cities are also planning to traffic trunk lines in 2010 to control noise at the average of less than 70dBA. According to the domestic current data indicate that the domestic value of bus noise permit shall not exceed 82dBA, light trucks for 83.5dBA. This shows that our country in the vehicle noise control will have to make do.
noise assessment noise evaluation mainly refers to the car, outside noise and vibration adaptive value. Evaluation methods can be divided into subjective evaluation and objective evaluation. Subjective assessment of the impact of vehicle noise is a major factor in comfort, loudness and uncertainties, such as semantic differential method can be used for subjective evaluation. At an objective evaluation, can be used PCNM noise measuring device for measuring test analysis; addition simulation technology in the finite element method (FEM) and boundary element method (BEM) has been widely applied.
noise control noise generation and dissemination in accordance with the mechanism of noise control technology can be put into the following three categories: First, the control of noise sources, are two routes of transmission of noise control, noise three recipients are protected. One of the control of noise sources are the most fundamental, the most direct measures, including noise reduction to reduce the exciting force and the engine parts of the exciting force response, which means transformation of acoustic source local oscillator. However, it is difficult to control noise sources when necessary in the route of transmission of noise to take measures, such as sound absorption, sound insulation, noise reduction, vibration and vibration isolation measures. Motor vehicles and vehicle vibration and noise reduction level of power, economy, reliability and strength, stiffness, quality, manufacturing costs and use are closely related.
engine to reduce vibration and noise of the engine noise is the focus
of automotive noise control. Engine vibration and noise are generated at source. Engine noise is from fuel combustion, valve bodies, gears and piston timing noise percussion synthesis.
(1) ontology engine noise
Lower engine noise will be ontological transformation of local oscillator sound sources, including methods such as finite element method analysis and design engines, selection of soft combustion process, improve the structure of the body stiffness, with the use of tight space, reduce noise cylinder cover. For example in the oil pan on an additional stiffener and diaphragm to improve the stiffness of oil pan to reduce vibration and noise. In addition, give the engine Tu damping material is an effective approach. Damping materials can kinetic energy into thermal energy. To deal with the principle of damping is a damping materials and components into its vibrational energy to consume. It has the following structure: Freedom damping layer structure, and spacing of freely damping layer structure, and constrained damping layer structure and spacing of constrained damping layer. It is clear that the adoption of a decrease of resonance amplitude and accelerated the decay of free vibration, reducing the various parts of the Chuan-Zhen capacity, an increase of parts at or above the critical frequency of vibration isolation capacity. At present, some countries have designed an engine experts active vibration isolation system to reduce engine vibration, in order to achieve the purpose of noise reduction.
(2) intake noise
Engine intake noise is one of the main noise source, the Department of the engine noise of air power, with the engine speed increases to strengthen. Non-supercharged engine intake noise major components, including the cyclical pressure fluctuation noise, vortex noise, the cylinder of the Helmholtz resonance noise. Diesel engine supercharger intake noise mainly from the turbocharger compressor. Two stroke engine noise from the Roots pump. In this regard, the most effective method is the use of intake muffler. There is a resistive type muffler (absorption type), resistant muffler (expansion type, resonance type, interference-type and porous decentralized) and the composite muffler.
To combine with the air filter (that is in the air filter on an additional resonance chamber and sound-absorbing material, for example, type R3238) has become the most effective intake muffler, muffler volume of more than 20dBA.
4.2 Chassis Noise
(1) Department of exhaust noise
Department of the chassis exhaust noise is the main noise sources, mainly from the exhaust pressure pulsation noise, air flow through the valve seat when issued by eddy current noise, because of boundary layer airflow disturbance caused by noise and exhaust Office jet noise composition.
Designed to optimize the performance of a good muffler, to reduce car noise are one of the important means. Optimize design method has acoustic finite element method and acoustic boundary element method, but is still in its infancy. Muffler to avoid the transmission characteristics and vibration characteristics of coupled mufflers are designed to be focused on solving a problem. Secondly, to reduce exhaust noise and improve power is also a pair of contradictions, because to reduce exhaust noise and lower exhaust back pressure on the design of the exhaust pipe has a diameter of conflicting demands, the former requires a smaller diameter, which is opposite . In this regard, the use of parallel flow path of the dual function muffler, at reduced air pressure and reduce noise to be effective. In addition, the engine exhaust manifold to the muffler inlet pipe section, the use of flexible pipe vibration, noise reduction effect can be reduced to about 7dBA.
(2) power train noise
Powertrain noise from the vibration caused by变速齿轮meshing and rotating shaft vibration. General measures taken are: First, choose low-noise transmission, engine and gearbox are two and the main reducer, such as rear axle and chassis components for flexible rubber pad connections, so as to achieve the purpose of isolation; are three-axis rotational control balance degrees, to reduce torsional vibration.
4.3 Electric equipment noise
(1) cooling fan noise
Cooling fan noise happened devices are subject to wind retaining ring, water pump, radiator and transmission, but the noise generated depends primarily on the chassis.
(2) automobile generator noise
Automotive generator noise depends on the effects of a variety of sources, these sources have magnet source, mechanical and air power source. Noise level depends on the generator magnetic structure and ventilation systems, as well as generators precision manufacturing and assembly.
4.4 Body Noise
As the speed increased, the body will be more and more noise, and air power are the main causes of noise. Therefore, the following programs to improve the body noise: First, to streamline the design of the body, achieve a smooth transition; two are in between the body and frame components to adopt a flexible connection; three interior is softened, such as Inner Mongolia at the roof and body skin the use of sound-absorbing material.
In addition, the car at high speed when the tire is also a source of noise. Real vehicle Inerting line method has been measured: Tire Tread greater, then the greater the noise. In addition, the tire tread with the noise generated also have a great relationship, there is a reasonable choice of the pattern of steel cord for radial tires to reduce tire noise are an effective way. Materials for the tire, the use of more flexible and soft rubber with high, you can create a low-noise tires.
4.5 Other measures
Automobile noise control, except in the design on the use of optimization methods and optimization of selected components, it can also carry out active control of noise. This is based on sound muffler technology, the principle is: the use of electronic muffler system with the opposite phase of the acoustic noise, vibration so that the two cancel each other out in order to reduce the noise. This muffler device used extremely advanced electronic components, has excellent noise reduction effect can be used to reduce vehicle noise, engine noise, the engine could also be used to proactively support systems, to offset the engine vibration and noise
随着汽车产业的快速发展，对车辆的舒适性、振动和噪声控制要求越来越严格。据有关资料表明，百分之七十的城市噪音来自交通产生的噪音，而交通噪音主要是汽车噪音。这对城市的环境污染非常严重，影响到人们的生活、工作和健康。。因此，控制汽车产生的噪声，不仅关系到舒适性，而且也与环境保护有关。另外，噪音来源于振动，而振动会导致汽车的某些部件过早的出现疲劳损伤，从而减少机动车的使用寿命; 过量噪音可损害司机的听力，司机在振动中非常容易迅速的疲劳驾驶，从而对安全构成严重的威胁。因此，噪声控制，也关系到汽车的耐用性和安全性。因此振动，噪声和舒适性是三个密切相关的因素，想要减少振动，降低噪音，提高乘坐舒适性并且确保汽车的经济性，车辆噪声必须控制在标准范围内。
由空气动力，机械传动，电磁三部分引起的噪音是汽车噪音的一种类型。从结构可分为发动机噪音（即燃烧噪声） ，底盘噪音（即传动系噪声，所有的组件噪声） ，电气设备噪音（冷却风扇噪声，汽车噪声发生器） ，机构噪音（如车身结构，形状和附件安装不合理的噪音） 。其中一个发动机噪声占了机动车一半以上的车辆噪声，包括发动机本身的噪声和车辆摄入噪声（如发动机振动，转动轴阀，进、排气门开关，如排气噪声等） 。因此，减少发动机振动，降低噪音已成为一个关键的汽车噪声控制。
此外，汽车轮胎在高速时，它也将带来更多的噪音。这是因为轮胎在地面流动的格局位于空中和地面之间，气流经过挤压被吸入轮胎，与轮胎花纹的撞击的声音。
在欧洲，对于汽车噪音有专门的法规要求，从1996年10月起，外部总噪音必须从77dBA 减少到74dBA ，噪音的减少了节约了一半的能源，在本世纪末进一步降低到71dBA 。日本也有相应的法律和规章，小型车在未来十年内，必须把噪音控制在76dBA 以下 。
国内的一些城市也计划在2010年交通干线上控制噪声平均值小于
70dBA 。根据国内目前的数据表明，国内驾驶巴士的噪音许可不得超过82dBA ，轻型卡车为83.5dBA 。这表明，我国在车辆噪声控制方面将越来越完善。
噪音的评估与噪音的评价主要是指车外噪音和振动自适应价值。评价方法可分为主观评价和客观评价。汽车噪音是一个影响舒适性的主要因素，对人体的感觉是不确定因素，主观评价于每个人来说是有差异的。而客观的评价则可以用PCNM 噪声测量装置测量测试分析; 此外仿真技术在有限元法（ FEM ）和边界元法（ BEM ）已得到广泛的应用。
控制噪音的产生和传播根据该机制的噪音控制技术，可以分为以下三类： 第一，控制噪声源，
第二，通过控制传播途径对噪声进行控制，
第三，对噪声的接受者即乘客和驾驶者进行保护。
而第一个控制噪声声源是最根本，最直接的措施，包括降低噪音，减少激振力和发动机部件对激振力的反应，这意味着转化声源本身的振荡。然而，这种噪声源是难以控制的，必要时对噪声的传播途径采取措施，例如利用吸声，隔声来减少噪音，采取振动和振动的隔离措施。车辆的振动和噪声对于机动车辆降低能耗水平，提高经济性、可靠性和强度、刚度、降低这两本身质量、制造成本和使用等密切相关。
控制汽车噪声的重点是减少发动机引擎的振动和噪音。引擎是发动机振动和噪声产生的源头。发动机噪声是由燃料燃烧，阀体，齿轮，活塞敲击缸体等噪音合成。
（ 1 ）发动机本体噪音
降低发动机噪音将本体论的转变，本地振荡器声源，方法包括：如有限元法分析和设计引擎，选择软燃烧过程，改善结构，提高材质的刚度，利用严格的空间安排减少间隙，降低气缸盖的噪声。例如在油底壳上额外加力和隔膜，可以改善油底壳刚度，以减少振动和噪声。此外，在发动机上涂阻尼材料也是一种有效的办法。阻尼材料能够把动能转化成热能。处理的方法是：一种阻尼减振材料，其部件吸收振动能量并转化成其他方式消耗掉。它具有以下结构：自由阻尼层结构，间隔自由阻尼层结构、约束阻尼层结构和间隔约束阻尼层。很显然，通过减少了共振振幅和加速衰变的自由振动，从而减少了各部分的传振能力，增加了部分达到或超过临界频率振动隔离能力。
目前，一些国家的专家设计的发动机主动隔振系统，以减少发动机振动，以实现降低噪音的目的。
（ 2 ）摄入噪音
发动机进气噪声是主要噪声源，该部份是发动机噪声的空军力量，随着发动机转速的增加而加强。非增压发动机进气噪音的主要组成部分，包括周期性压力脉动噪声，涡流噪声，汽缸的亥姆霍兹共振噪声。
柴油机增压器进气噪音主要来自涡轮增压压缩机。在这方面，最有效的方
法是使用多种消声器。有一个电阻型消声器（吸收型） ，抗性消声器（膨胀型，共振型，干涉型和多孔分散）和复合消声器。结合了空气过滤器（即在空气过滤器的额外共振和吸声材料，例如，输入R3238 ）已成为最有效的消除摄入噪音的消声器，通过消声器消音可超过20dBA 。
4.2底盘噪声
（ 1 ）底部排气噪声
底部的主要噪声源于底盘排气噪声，主要是来自排气压力脉动噪音，空气流经阀座时发出的涡流噪声，由边界层气流扰动所造成的噪音和排气管喷气噪声组成。
在其排气管道使用性能良好的消声器，是减少汽车噪音的重要手段之一。优化设计方法有声学有限元法和声学边界元法，但这两种方法仍处于初级阶段。以避免传播特性和振动特性的耦合消声器的目的是把重点放在解决问题。
首先，着眼于解决问题。
其次，降低排气噪声和改善电源也是一对矛盾，因为，以减少排气噪声和降低排气背压时设计的排气管的直径二者是相互冲突的两种要求，前者需要直径越小越好，这是一方面，在这方面，使用平行流路的双重职能消声器，以降低空气压力和降低噪声是有效的。此外，发动机的排气管消声器进入排气管，使用灵活的管道振动，降低噪声的影响可降低到大约7dBA 。
（ 2 ）动力总成噪声
造成动力总成的振动噪音是变速齿轮啮合和旋转轴振动。一般采取的措施是：第一，选择低噪音的传播途径，连接发动机的是变速箱和两个主要减速器，如后轴和底盘的部件用灵活的橡胶垫连接，从而实现分离的目的; 有三个轴转动的要控制平衡度，以减少扭振。
4.3电气设备噪声
（ 1 ）冷却风扇噪音
冷却风扇噪声发生设备受风护环，水泵，水箱和传输的影响，但所产生的噪音主要还是取决于底盘。
（ 2 ）汽车发电机噪声
汽车发电机噪声的影响取决于各种不同的来源，这些来源有磁铁源，机械
和空气动力源。噪音水平取决于发电机磁结构和通风系统，以及发电机，精密制造和装配。
4.4车身噪声
随着汽车速度的增加，车体将被越来越多的噪音所打扰，空气阻力是噪音的主要原因。因此，增加以下程序，以改善身体噪音：第一，精简机构的设计，实现平稳过渡; 身体和框架两者之间的的组成部分，采取一种灵活的连接; 三个内部进行软化，如内蒙古的屋顶和主体外面的材料使用吸声材料。
此外，赛车在高速时的轮胎也是一种噪音来源。实车惰化线法进行了测试：轮胎的横截面积越大，那么噪音就越大。此外，胎面的材料与所产生的噪音也有很大的关系，现在有一个合理的选择的模式就是用用钢丝帘线的子午线轮胎，以降低轮胎的噪声，这是降低噪声的一种非常有效途径。
这种材料的轮胎，使用更加灵活，软橡胶含量很高，以此可以创建一个低噪的音轮胎。
4.5其他措施
汽车噪声控制虽然不是很具有确定性，但在设计上使用最优化方法和优化的选定部分，它也可以进行主动控制噪音。这是基于良好的消声器技术，其原理是：利用电子消声系统与相对阶段的噪声，
两个能够相互抵消的振动，可以以减少噪音。这种消声器装置采用非常先进的电子元件，具有良好的降噪效果可用于减少汽车噪音，发动机噪音，发动机也可以用来积极支持系统，以抵消发动机的振动和噪声。