【作者】 周堃；

【导师】 赵玉涛；

【作者基本信息】 江苏大学 ， 材料学， 2009， 硕士

【摘要】 铸造过程计算机模拟与仿真同结构有限元分析技术是信息科学、材料科学、工程力学及计算机图形学等各种学科的交叉科学,是先进制造科学的重要前沿领域。针对传统凭借经验设计制造车轮的过程中存在设计造型盲目性大、铸件成品率低、检测周期长的问题,本论文采用了计算机辅助造型技术及有限元分析方法,研究了车轮从初始造型设计到铸件生产过程数值模拟,最后到产品结构疲劳性能分析的全过程,这样能够迅速发现产品设计和生产中存在的问题,通过优化设计,提高产品成品率同时改善结构薄弱环节以缩短开发周期、降低成本,主要研究内容如下:1、详细分析了车轮造型设计的组成要素,考虑了车轮造型设计中所涉及的各种要求和标准,并通过三维造型技术对车轮实体建模,在此基础上归纳总结了现代CAD建模技术的特点。2、结合SU0011车轮的开发和制造要求,对其实际低压铸造过程进行了数值模拟,计算了车轮充型和凝固过程中的流场和温度场,预测了缩孔、缩松等缺陷,并就缺陷产生原因进行了分析,然后提出改进方案,优化了产品制造工艺,满足高铸造成品率的实际生产要求。3、针对结构优化设计过程中忽略的残余应力问题进行了分析,计算了车轮铸件的铸造残余应力,通过开发的接口程序将车轮的有限元网格信息和残余应力信息输入到ANSYS中,利用ANSYS的结构分析模块对车轮进行了加载计算,模拟了含有铸造残余应力的车轮在装车后形成的初始应力现象。这样的分析更符合铸件的实际生产情况,对后续的工作具有指导性意义。4、对铝合金车轮的弯曲疲劳强度试验进行了数值模拟,根据实际工况建立起车轮的有限元模型,在考虑铸造残余应力的基础上研究了螺栓预紧力、旋转离心力和试验弯矩对车轮结构强度的影响以及车轮结构的应力应变分布规律。同时,利用动态应变仪采集危险点的应力信号分析实际应力分布状态,结果表明:计算值与实测值间误差只有4%,有限元计算结果准确可靠,车轮结构能够满足强度的使用要求,利用有限元技术从结构使用强度上证明了车轮设计的合理性,同时对车轮结构的薄弱环节提出了修改方案,对车轮结构进行优化设计,做到节省材料的同时改善受力状况。经某车轮有限公司的实际验证,本文进行的汽车铝合金车轮的造型设计、低压铸造过程数值模拟及工艺优化和疲劳强度模拟验证的研究工作,具有很好的应用性、较大的通用性和工程实践价值,在合作项目中,取得了较大的经济效益。更多还原

【Abstract】 Wheel is one of the most important parts in the driving system of automobile.It greatly affects the security and reliability of the car.We used to design wheels by experience.But it has many disadvantages,such as the blindness in design,the long period,the high cost and soon.The enterprises want exigent to improve the way because of the more and more intense competition.We build a platform about Design and Production of Aluminum Alloy Wheel Aided by Computer.Through Numerical Simulation,which provides the improving solution,the casting process is optimized. The preparation time for process is dramatically shortened and the cost of trial-production is reduced,saving valuable time for obtaining satisfactory percent of pass of the new model wheel.1.The conception of "Industrial Design" is applied to design the wheel.The methods and skills in the presentation of thoughts in modeling of the modeling design combine with the GB/T 3487-2005 tie the engineering technology and the presentation of artistic molding in perfectly.2.According to the process requirement of ProCAST for castings to be supplied to wheel,The basic model block and fluid analysis model block are applied to analyze fluid,temperature and stress when the casting is solidifying so as to predict shrinkage, dispersed shrinkage and other defects of these castings,being a scientific base for bogie castings manufacturing.3.Receive the residual stress of the wheel by the Stress Analysis module block of ProCAST software.Date exchange program is compiled.Node、element and the stress tensor at the node files are transmitted into ANSYS(a large-scale FEM software) using the Interface program.Then the structure of the wheel is analyzed by the structure module of ANSYS.Simulate the "initial dynamic stress" phenomenon of assambeled wheel.Through this mode,the wheel with residual stress can be analyzed when we load other weight on it.The results are more accurate than the one without residual stress.4.The structural strength is the key point to describe the quality of a wheel. Since the cornering test fails more frequently among the three,this paper applies CAE technology to analysis the structural strength under the condition of cornering test.The model of the aluminum alloy wheel is built.Stress analysis is carried out to study the influence of bolt pre-tension,centrifugal force and the cornering force to the structural as well as the distributing rule of stress and strain.To validate the result of CAE,the stress test is carried out.Compared with the collected stress,it proved that the error between them is just 4%.So the analysis model is correct and the result is credible.The research of modeling design,technique optimization、strength analysis and fatigue life prediction of aluminum alloy wheel possess versatility and practical value and obtain the huge economy benefit and engineering value in the project with an Auto company.更多还原