轻型载货汽车车架有限元静力学分析

摘要

汽车车架作为汽车总成重要的一部分，车辆受到来自道路和装载的各种复杂载荷最终都会传递给车架，并且汽车上许多重要总成都是以车架为载体，因而车架的强度和刚度在汽车总体设计中起了非常重要的作用。因此，车架结构性能的好坏关乎这整车设计的成败。若用传统经典力学方法计算，结果失真太大；而用试验法进行测试，成本高，周期长。为此本文采用了有限元分析技术，来实现车架结构设计合理化和轻量化的目的从而大大减少设计费用，缩短设计周期，同时提高设计工作的效率。因为，ANSYS在对实体模型分析上具有强大的功能，在结构静力学分析以及优化设计方面相比很多其他软件拥有十分明显的优越性。本文利用三维建模软件Pro/E和有限元分析软件ANSYS对某轻型载货汽车车架进行了Pro/E建模和ANSYS分析。

通过对Pro/E和ANSYS软件的的了解和学习，采用Pro/E实体建模，导入ANSYS 进行网格划分，应力加载，求解得出经动态分析结果，得出结论，之后可根据需要对已设计的实体单元为基础的车架结构进行拓扑优化模型和简单的尺寸优化模型，以车架的纵梁截面尺寸为设计变量，以车架结构的总体积最下为优化目标，对车架纵梁截面尺寸进行优化并分析优化结果。通过对初步设计出的轻型车架结构的实体建模及有限元分析，得到一些对车架设计有所帮助的结论，为今后车架的设计工作提供一定的指导作用。

关键词：轻型货车车架；三维建模；载荷；有限元静力学分析；模态分析

ABSTRACT

Automobile frame, as an important part of the vehicle, the vehicle being loaded from the road and the complex will eventually be passed to the load frame, and the car is the frame number of important general in Chengdu as the carrier, and thus the strength and the framestiffness of the overall design of the car plays a very important role.Therefore, the performance is good or bad frame structure about the success of this vehicle design.If the traditional method of classical mechanics, the result is too large distortion; and tested using test method, high cost and long period.To this end this paper, the finite element analysis, design of the frame structure to achieve the purpose of rationalization and lightweight thus reducing design costs and shorten design cycles, while improving the efficiency of design work.Because, ANSYS solid model in the analysis of powerful features in the structure of static analysis and design optimization software, compared with many other obvious advantages.In this paper, three-dimensional modeling software Pro / E and the finite element analysis software ANSYS, a light truck chassis is a Pro / E modeling and ANSYS.

On Pro / E and ANSYS software, understanding and learning, the use of Pro / E solid modeling, meshing into ANSYS, the stress load, obtained by solving the dynamic analysis of the results, draw conclusions, and then as needed for. The solid element has been designed based on the topology optimization of frame structure model and the size of a simple optimization model to frame the longitudinal cross-section dimensions of design variables, the total volume of the frame structure to optimize the next goal, on the framelongitudinal section size optimization and analysis of optimization results.The preliminary design by a light frame structure of solid modeling and finite element analysis, get some help on the conclusions of the frame design, frame design for the future to provide some guidance.

Key words：Frame of track; Three-dimensional modeling; loads; Finite element static analysis; Modal analysis