文档介绍：重庆理工大学
硕士学位论文
某全地形车车架轻量化研究
姓名:王喻
申请学位级别:硕士
专业:车辆工程
指导教师:陈旭
2011-05-24
摘要
随着国际能源危机的加剧,国家对节能减排的要求不断提高,加之各种电动车、
电动自行车的白热化竞争,摩托车企业所面临的竞争压力空前加剧。运用轻量化技术,
降低消费者的使用成本,提高产品的市场占有率,已成为摩托车企业应对市场竞争,
稳固市场地位的重要手段之一。车架作为全地形车的主要支承构件,也是全地形车的
主要总成之一,在整车轻量化中占有十分重要的作用。
论文以某企业某型号全地形车车架为研究对象,在满足车架所能承受的强度、刚
度和一阶频率的前提下实现车架的轻量化。
在研究过程中,以原车架为参考对象,采用有限元法,分析其使用过程中出现的
弯曲工况、扭转工况、跌落工况和自由模态工况,验证项目的可行性。
模态试验以原车架为实验对象,采用锤激模态实验方法,运用
软件对所测数据进行分析,得出实验模态的模态频率和振型,并和计算模态进行分析
比较,检验有限元模型是否正确,其分析结果是否值得信赖。
根据最优化设计理论,选择车架的轻量化设计方案,设计变量为车架各零件厚度,
目标函数为车架总体积,约束条件为强度、刚度和一阶频率,建立车架优化的数学模
型。基于结构优化软件 OptiStruct 对其车架各设计变量进行尺寸优化,达到减轻质量
5Kg,减重 16%的目的。
对优化后的车架进行校核,验证车架的应力分布趋于平均,强度和刚度符合要求,
车架的一阶模态频率避开了车辆常用车速下的共振频段。
通过运用优化设计技术对该款全地形车车架进行轻量化设计,降低了车架的质
量,提高了该款车型的运动性能和燃油经济性。
关键词:车架,有限元,实验模态,结构优化,轻量化
I
ABSTRACT
Under the crisis of the increasing shortage of international energy, with the constantly
increasing national demand of energy conservation and emissions reduction, and facing
peting by kinds of electric cars, electric bicycles and motorcycles, motorcycle
enterprises are trapped in another rival who have never appeared in the past. It is one of the
most important measures for motorcycle enterprises to reduce the cost of consumers,
improve the market shares of products and consolidate market position by using
lightweight technology. The frame, which is the main ponents and the
important assembly of the all-terrain vehicles, plays an important role of the vehicle
lightweight.
In the paper, we took some enterprise a certain type of all-terrain vehicle frame as the
research object, and reduced the frame’s weight under the limit of meeting the frame’s
strength, stiffness and first-order frequency.
In the process of researching, we took the original frame as reference object. Based on
the finite element, we analyzed four work conditions, called bending condition, torsion
condition, drop condition, and free modal condition. Throughout the ana