换挡拉索对变速器啸叫噪声影响的研究

变速器啸叫噪声可以通过换挡拉索传递到车内,影响车内乘员的舒适感觉。用切断传递路径的方法研究了换挡拉索对变速器啸叫噪声的影响,并结合实际的试验,优化换挡拉索端部的结构,阐明了降低拉索传递振动的方法。     

汽车变速器振动啸叫噪声实验研究

汽车变速器啸叫噪声是变速器常见的问题.对变速器啸叫噪声进行测试与分析,提出变速器啸叫噪声的客观评价,形成变速器啸叫噪声测试分析流程.     

基于EXCITE PU的某重型变速器啸叫噪声模拟优化

本文针对重型变速器啸叫噪声,通过耦合有限单元法和多体动力学方法,使用AVL—EXCITE Power Unit软件搭建了某重型变速器振动仿真模型,并与该变速器振动试验对标,模拟结果复现了齿轮的啸叫噪声。基于齿轮修形理论,采用KISSOFT软件对齿轮进行齿面微观修形,进而对变速器啸叫噪声优化,形成变速器啸叫噪声优化模拟方法。研究结果表明,齿轮微观修形可以减小传递误差,对啸叫噪声起到明显的改善效果。     

变速器高速啸叫问题的分析与改进

变速器作为汽车的核心零部件,对变速器的研究直接影响到整车的NVH水平,在整车开发过程中变速器NVH性能为整车性能的一个重要指标.对变速器传递路径的机制进行了分析,并制定了变速器壳体增加加强筋和优化变速器齿形参数的方案.经过仿真分析、主观驾评、客观测试均证明车内阶次噪声改善明显,该方法能够有效解决变速箱啸叫问题.     

某乘用车手动变速器齿轮啸叫噪声研究

为解决某乘用车手动变速器存在的齿轮啸叫噪声问题,首先通过整车道路试验和变速器台架试验,识别出产生齿轮啸叫噪声的特征阶次及转速,然后建立该手动变速器齿轮传动系的多体动力学模型,考虑各对齿轮的时变啮合刚度、齿侧间隙、啮合阻尼,仿真获得了轴承动态载荷。利用在二挡工况下获得的变速器各轴承动载荷,采用有限元及边界元法计算了变速器壳体的振动响应及辐射噪声,并利用试验测得的结构表面振动加速度进行了试验验证。仿真获得了变速器壳体主要噪声源位置,为降低齿轮啸叫噪声提供了依据。     

基于整车传递路径贡献分析法的纯电动车啸叫噪声优化

针对某电动车的车内啸叫噪声,利用逆矩阵法提取问题工况下各激励点载荷,搭建车内啸叫的传递路径贡献量分析模型。根据分析结果,确认啸叫噪声的主要路径并针对该问题路径提出相应改善措施,将电机隔振系统设计成二级隔振系统;搭建刚柔耦合仿真模型,以隔振器的刚度为优化变量,以问题路径的振动传递率为优化目标,对电机隔振系统进行优化。按照优化结果进行装车试制,经实车试验验证,车内啸叫问题得到明显改善。     

车辆变速箱啸叫噪声测试诊断

在汽车NVH研究范围内,动力总成相关的噪声振动一直是研究的一个重要方面,同时也一直是研究的一个困难课题.其原因为该噪声振动往往必须通过正向的动力总成相关部件研究及设计修改来确诊原因并且最终解决问题.通过一个实际案例介绍如何使用阶次分析原理和传递路径分析方法对车辆变速箱的齿轮啸叫噪声进行测量及诊断,根据文中的测试诊断结果...     

圆锥滚子轴承预紧力对变速器啸叫噪声的影响分析

基于仿真分析和实验方法研究了轴承预紧力对汽车变速器啸叫噪声的影响,建立了六挡机械式变速器动力学仿真模型,分析了副轴-后轴承采用不同的预紧力对系统动力学性能的影响,主要考察了传动误差激励、动态啮合力和轴承力变化,获得了不同的箱体动态响应。利用阶次跟踪方法进行实验,分析了不同预紧条件下的振动加速度和声压级水平。结果表明：采用合理的预紧力时,增大轴承刚度有助于抑制变速器啸叫噪声的产生,仿真分析与实验结论一致。     

车内噪声传递路径分析方法探讨

为了指导汽车NVH工程师更好地进行故障诊断和声学设计,介绍了传递路径分析（TPA）方法的基本原理,详细分析传递函数和激励力的测量方法,并以某型汽车发动机振动噪声向车内传递为例,介绍TPA方法的应用。试验结果表明,应用TPA方法可有效、方便地进行噪声源识别和贡献分析。     

汽车变速器啸叫噪声源识别与分析

通过某款五档手动变速器二档啸叫噪声改善实例的介绍,探讨了噪声问题改进的工作方法,根据整车NVH或振动噪声台架测试识别噪声源,分析噪声激励性质和成因,确定通过降低档位齿轮传递误差和啮合冲击来改善噪声的思路,制定齿轮微观修形方案,改善齿轮承载状态的啮合接触,有效降低啸叫噪声。     

基于传递路径分析的车内噪声源识别

简述了车内噪声的产生机理和传递路径分析试验的基本原理.针对某国产试制SUV在怠速和三档急加速工况下车内噪声偏大的问题,建立传递路径分析模型,进行传递路径分析试验.根据试验结果识别出车内噪声的主要传递路径,找出主要传递路径贡献量大的具体原因.最后提出降低车内噪声的修改建议,为降低车内噪声提供依据.     

Operational transfer path analysis: Theory,guidelines and tire noise application

The operational transfer path analysis (OTPA) method is the subject of research in this article, which starts with a discussion on it's theory. Here clear similarities with the MIMO technique in experimental modal analysis are found. Based on the knowledge of MIMO, one finds that input signals are allowed to be coherent to a certain extend. As coherence can be larger in OTPA in practice, the method is extended with the singular value decomposition method to reduce influences of noise. The article proceeds with a discussion on points of attention, or boundary conditions, in practical applications. An analysis on tire noise is included to illustrate the points of attention and the methods strength in, for example, vehicle TPA on tires.     

Operational transfer path analysis

One of the tools used to study the NVH behaviour of a system is the transfer path analysis. It aims to identify the operational forces and the propagation paths of the vibrations and is especially interesting in the case when the system is composed of different subsystems. The classical techniques identify the transfer paths when the system is disassembled. This way one eliminates flanking transfer paths. Yet it is very time-consuming and the boundary conditions are not correct anymore. The presented method makes it possible to identify the transfer paths without disassembling the system. The advantages are that the overall testing time is reduced and that the real boundary conditions are present. In this article the theory will be reviewed and it will be validated using data generated by finite element simulations.     

某变速箱某挡位噪声源定位的试验分析

本文通过对某变速箱某挡位发出的噪声进行噪声振动试验研究和分析,在振动噪声特性分析的基础上,依据振动与噪声发生的机理,比照振动噪声谱与齿轮啮合频率的对应关系,辨析该挡位噪声产生的原因和传递路径,为降低噪声提供设计改进的依据。     

新型传递路径分析OPAX方法研究

OPAX （Operational-X Transfer Path Analysis）法是一种新型的传递路径分析方法,利用已有的数据拟合出耦合点的激励力,计算出各路径对目标点的贡献量,从而可进行传递路径分析.它具有高效率、高精度的特点.以某中型客车为研究对象,利用OPAX法对其进行了结构传递路径分析,识别出主要贡献路径,然后采取相应措施对悬置进行改进,且取得了良好效果.     

Application of the transmissibility concept in transfer path analysis

In recent years, there has been a renewed interest in developing faster and simpler transfer path analysis (TPA) methods. A dominant class of these new approaches, often referred to as Operational Path Analyses (OPA), is designed to achieve this goal by using only operational data in conjunction with the application of the transmissibility concept. Despite the reduction in measurement time and complexity, these suffer from a number of limitations, such as problems related to the estimation of transmissibility, or the unreliability of the results due to cross-coupling between path inputs, etc., which makes them prone to errors. Some of these only apply to one specific method, while others are common to all transmissibility based approaches. The goal of this paper is to identify and describe these limitations and point out the potential dangers of applying such methods without taking these into account.     

基于阶次分析的客车变速器噪声试验

基于德国米勒贝姆振动与声学系统公司开发的PAK振动噪声测试分析系统,应用其阶次分析功能对某五挡客车自动变速器的噪声进行实车试验,得到不同挡位下车厢声压级的组成及变化情况.结果证明阶次分析方法能够准确地识别变速器的噪声源.     

Transmission path analysis of noise and vibration in a rotary compressor by statistical energy analysis

The hermetic rotary compressor is one of the most important components of an air conditioning system since it has a great effect on both the performance and the noise and vibration of the system. Noise and vibration occurs due to gas pulsation during the compression process and to unbalanced dynamic force. In order to reduce noise and vibration, it is necessary to identify their sources and transmission path and effectively control them. Many approaches have been tried in order to identify the noise transmission path of a compressor. However, identification has proven to be difficult since the characteristics of compressor noise are complicated due to the interaction of the compressor parts and gas pulsation. In this study, the statistical energy analysis has been used to trace the energy flow in the compressor and to identify the transmission paths from the noise source to the exterior sound field.     

AR model-based crosstalk cancellation method for operational transfer path analysis

Journal of Mechanical Science and Technology - To reduce the crosstalk effects between the signals at reference points in operational transfer path analysis (OTPA) and improve the reliability of...