共查询到20条相似文献,搜索用时 62 毫秒
1.
2.
3.
4.
5.
在车身骨架结构方面,前围骨架对车身的整体刚度,振动特性等方面影响很大,尤其在典型的开式壳体中,其作用更为显著。本文就前围骨架的构造、功能作了一些分析,指出该总成及其附装部件的刚度对车身整体刚度的影响,以及从结构上改进汽车某些性能的可能性。 相似文献
6.
7.
《汽车工程》2017,(11)
建立了某SUV白车身有限元模型,对车身静态刚度和模态分布进行优化,改善了白车身的振动性能。通过灵敏度分析筛选白车身关键部件的厚度并将其作为优化变量,以车身的扭转刚度和质量作为目标,建立其径向基函数模型,将静态刚度、车身1阶扭转和1阶弯曲模态频率作为约束条件,并利用多目标遗传算法对车身性能进行优化。试制了优化后白车身关键部件,并进行模态试验,验证了优化结果的正确性。优化后在总质量增加0.55%的情况下,提升了车身整体刚度,改善了模态频率分布,后排左、右侧座椅安装点的传递函数峰值分别下降了47.50%和49.37%,极大地改善了车身振动性能,为整车NVH性能的提升打下良好基础。 相似文献
8.
引入振动载荷传递路径上系统刚度的概念,梳理了车身刚度的分类和物理意义。明确了整体静刚度及连接点的局部静刚度、动刚度是提升系统刚度的关键。并通过介绍某车型的具体案例,研究了如何通过优化车身刚度,特别是车身局部刚度来提升汽车操纵稳定性。 相似文献
9.
10.
某SUV四驱车加速过程中在发动机转速为3800 r/min时车身前地板振动明显,严重影响车内乘坐舒适性。基于车身模态的频率响应,本文着重对车身动力总成悬置安装点进行了频响特性分析;根据分析结果,找出车身局部动刚度不足的原因,对安装点局部结构进行优化,消除了频响曲线中峰值,解决了车身动力总成悬置安装点动刚度不足的问题,对车身动力总成悬置安装点或其它局部的动刚度优化供了一定参考价值。 相似文献
11.
12.
13.
14.
《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(9):1403-1421
Damage to the surface of railway wheels and rails commonly occurs in most railways. If not detected, it can result in the rapid deterioration and possible failure of rolling stock and infrastructure components causing higher maintenance costs. This paper presents an investigation into the modelling and simulation of wheel-flat and rail surface defects. A simplified mathematical model was developed and a series of experiments were carried out on a roller rig. The time–frequency analysis is a useful tool for identifying the content of a signal in the frequency domain without losing information about its time domain characteristics. Because of this, it is widely used for dynamic system analysis and condition monitoring and has been used in this paper for the detection of wheel flats and rail surface defects. Three commonly used time–frequency analysis techniques: Short-Time Fourier Transform, Wigner–Ville transform and wavelet transform were investigated in this work. 相似文献
15.
介绍了工程经济分析的主要内容,论述了微观与宏观经济分析之间异同点及相互关系,在此基础上提出随着我国公路建设新特点的出现,加强公路工程建设项目的经济分析,具有重要指导及实践意义。 相似文献
16.
以某款商用车驾驶室为研究对象,参照ECER29的相应规定,建立了摆锤和驾驶室的有限元模型及摆锤撞击的仿真模型,对某商用车进行前摆锤碰撞模拟分析。通过对过程能量的验证证明了模型本身的正确性。对主要部件的变形及吸收能量的分析,总结出了影响碰撞结果的主要因素,对该商用车的前摆锤碰撞假人生存空间进行了定量评价,在仿真分析中验证了该商用车的安全性。 相似文献
17.
18.
《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(3):443-459
In recent years, several authors have proposed ‘easier numerical methods’ to find the critical speed in railway dynamical problems. Actually, the methods do function in some cases, but in most cases it is really a gamble. In this article, the methods are discussed and the pros and contras are commented upon. I also address the questions when a linearisation is allowed and the curious fact that the hunting motion is more robust than the ideal stationary-state motion on the track. Concepts such as ‘multiple attractors’, ‘subcritical and supercritical bifurcations’, ‘permitted linearisation’, ‘the danger of running at supercritical speeds’ and ‘chaotic motion’ are addressed. 相似文献
19.