卧式加工中心整机的静动态有限元分析

利用有限元分析软件ANSYS对加工中心整机进行静力学分析和模态分析,得到其各主要部件的刚度和固有频率、固有振型.在此基础上计算了动静态特性,根据计算结果对其结构进行改进设计和优化.     

卧式加工中心模态分析与测试

结合面是影响整机动态特性的重要因素。对结合面的正确处理是研究整机特性的关键。首先,以TH6350卧式加工中心为对象。其次,采用合理的方法对四种不同类型的结合面进行等效处理,建立了整机有限元模型。然后,采用ANSYS有限元分析软件分析了整机的模态特性。最后采用锤击激振法对TH6350卧式加工中心进行了模态试验。通过对比试验结果与ANSYS分析结果,发现二者数据非常接近。从而验证了前期结合面处理的正确性与合理性,建立的有限元模型能真实地反映整机性能。     

高速龙门式加工中心模态分析

建立了高速龙门式加工中心的模态分析有限元模型。通过对该模型模态分析计算,并展开模态实验,分别得到了前四阶固有频率和相应的振型。计算结果与模态实验结果相比较,检验了有限元模态分析与实验模态分析两种方法。     

立式加工中心整机动态特性的测试与分析

系统地阐述了与有限元法相结合的模态试验分析方法。首先利用ANSYS Workbench对加工中心进行有限元模态分析,根据模态分析结果和具体情况布置模态试验激振点和测振点,然后采用单点激励多点响应模态试验分析方法来获取完整模态参数,引入相干性函数分析测试信号的可靠性。最后通过模态试验结果和有限元计算结果对比分析,准确识别出加工中心关键振型的模态参数,为加工中心的动态优化设计提供可靠的基础。     

XH6650加工中心动态仿真与模态测试分析

随着机床加工速度的提高,对机床的动态特性要求越来越高,文中以XH6650的高速卧式加工中心为对象,提出了简化结构细小特征,建立界面特性的有限元建模方法,建立了该机床的数字化模型,并进行动力学仿真,为验证建模方法的可靠性,对整机进行了动态测试,结果表明该方法有很好的精度.     

数控加工中心横梁有限元分析

本课题主要研究的内容是利用有限元分析方法和优化技术在确保结构安全可靠的前提下使结构更加合理;在保证结构有足够的强度、刚度和稳定性的条件下,节省材料消耗,降低产品成本;建立一种普遍适用于结构的有限元分析模型,研究和探讨分析的结果;通过、横梁结构的有限元模态分析,探索提高、横梁结构动态性能;将有限元分析方法与最优化技术相结合,克服优化设计中数学建模的困难,利用机械行业功能强大的Solidwork图形软件,从工程应用的角度出发,研究和开发一套实用的、高效的结构优化设计方法。最终,通过这些方法来改善FW系列数控加工中心的重量以及动态性能,以满足工业生产需要。     

柴油机缸盖结构有限元模态分析和模态测试

利用有限元分析软件ANSYS对造型十分复杂的某发动机缸盖结构建立了有限元模型,而后进行了自由模态分析计算,得到了该缸盖结构的低阶振动模态频率与模态振型.为验证模态分析模型的正确性,对该缸盖结构进行了模态试验测试,用锤击法对缸盖结构进行振动激励,利用测试软件获取缸盖结构的低阶振动模态频率与振型.通过有限元模态分析与模态测试结果的对比,验证了有限元模态分析模型与结果合理性,为该类型发动机缸盖结构设计与优化提供了参考依据.     

柴油机体结构有限元模态分析和模态测试

为了解决某科研项目问题,需要利用有限元分析软件ANSYS对某柴油发动机机体结构建立有限元模型,并进行自由模态分析计算,从而得到该机体结构的低阶振动模态频率与模态振型。在得到有限元模型后需要对该机体结构进行模态试验测试加以对比验证。通过有限元模态分析与模态测试结果的对比,验证了有限元模态分析模型与结果的合理性,为该类型发动机机体结构设计与优化提供了参考依据。     

曲轴-飞轮组合有限元模态测试和模态分析

根据与广西玉柴机器股份有限公司合作项目的要求,对曲轴-飞轮组合进行试验模态分析获取其固有频率、振型和阻尼,对建立的模型进行有限元模态分析,将计算结果与试验结果对比分析。通过有限元模态分析与模态测试结果的对比,验证了有限元模态分析模型与结果合理性。     

螺旋锥齿轮虚拟加工及有限元分析

根据传统式机床的结构特征和运动原理,用Catia对螺旋锥齿轮进行虚拟加工,通过和理论模型对比加工精度,证明建模的合理性和精准性.用Hypermesh对齿轮进行网格划分,导入Abaqus中进行有限元分析,提取传动误差曲线和接触线.随着载荷的增大,齿轮的传动误差波动幅值随之减小,但偏离零线的幅度随之增大,表明螺旋锥齿轮在载...     

正交切削高强耐磨铝青铜的有限元分析

采用热力耦合、平面应变、连续带状切屑的切削模型模拟了高强耐磨铝青铜的正交切削加工过程。采用增量步移动刀具的方法,结合有限元分析软件Marc的网格重划分功能,模拟了刀具从初始切入到切削力和切削温度达到稳态的切削加工过程,获得了不同切削深度和切削速度下的切屑形态、温度、应力、应变和应变速率的分布。并将模拟计算得到的切削力和切削温度与试验结果进行了比较,两者具有较好的一致性。     

MACHINING STUDIES OF UD-FRP COMPOSITES PART 2: FINITE ELEMENT ANALYSIS

A number of parameters and an exhaustive material development and experimental procedure to determine the response variables like cutting forces, surface damage restricts the expensive experimental research. In this context, Finite Element Method (FEM) analysis can be used as a tool for the prediction of the various machining responses. A finite element analysis of the orthogonal machining of Uni-directional Glass Fiber Reinforced Plastic (UD-GFRP) laminates is presented in this study to understand the complex relation between fiber orientation, tool geometry, depth of cut on cutting forces and sub-surface damage.     

MACHINING STUDIES OF UD-FRP COMPOSITES PART 2: FINITE ELEMENT ANALYSIS

ABSTRACT

A number of parameters and an exhaustive material development and experimental procedure to determine the response variables like cutting forces, surface damage restricts the expensive experimental research. In this context, Finite Element Method (FEM) analysis can be used as a tool for the prediction of the various machining responses. A finite element analysis of the orthogonal machining of Uni-directional Glass Fiber Reinforced Plastic (UD-GFRP) laminates is presented in this study to understand the complex relation between fiber orientation, tool geometry, depth of cut on cutting forces and sub-surface damage.     

UNDERSTANDING OF FINITE ELEMENT ANALYSIS RESULTS UNDER THE FRAMEWORK OF OXLEY'S MACHINING MODEL

We introduce an accurate coupled thermo-mechanical finite element analysis (FEA) of machining using the Arbitrary Lagrangian Eulerian (ALE) analysis capability of ABAQUS/Explicit. This analysis provides detailed information about the cutting forces, chip thickness, contact length, the extent of the primary and secondary shear zones as well as the distribution of strain, strain rate and temperature in the deformation zones. This information has to be viewed under the framework of an analytical model for it to lead to better understanding of the physics of machining. We use the best available analytical model, namely, Oxley's machining model, for this purpose and the FEA results are compared with the assumptions and predictions of Oxley's analysis. The strain rate in the primary shear zone, the hydrostatic pressure variation along the shear plane, the distribution of normal and shear stresses along the tool-chip interface and the shape of the secondary shear zone are the quantities compared. Due to the key role of temperature in the prediction of tool wear, the fraction of heat conducted away into the workpiece, the maximum temperature along the tool-chip interface and the maximum temperature along the flank face are also compared. The comparison reveals that Oxley's model captures the physics of machining quite well. However, some details such as the heat partition module and the assumptions on stress and temperature distribution at the tool-chip interface need to be revisited.     

UNDERSTANDING OF FINITE ELEMENT ANALYSIS RESULTS UNDER THE FRAMEWORK OF OXLEY'S MACHINING MODEL

ABSTRACT

We introduce an accurate coupled thermo-mechanical finite element analysis (FEA) of machining using the Arbitrary Lagrangian Eulerian (ALE) analysis capability of ABAQUS/Explicit. This analysis provides detailed information about the cutting forces, chip thickness, contact length, the extent of the primary and secondary shear zones as well as the distribution of strain, strain rate and temperature in the deformation zones. This information has to be viewed under the framework of an analytical model for it to lead to better understanding of the physics of machining. We use the best available analytical model, namely, Oxley's machining model, for this purpose and the FEA results are compared with the assumptions and predictions of Oxley's analysis. The strain rate in the primary shear zone, the hydrostatic pressure variation along the shear plane, the distribution of normal and shear stresses along the tool-chip interface and the shape of the secondary shear zone are the quantities compared. Due to the key role of temperature in the prediction of tool wear, the fraction of heat conducted away into the workpiece, the maximum temperature along the tool-chip interface and the maximum temperature along the flank face are also compared. The comparison reveals that Oxley's model captures the physics of machining quite well. However, some details such as the heat partition module and the assumptions on stress and temperature distribution at the tool-chip interface need to be revisited.     

MODAL TESTING AND FINITE ELEMENT MODELLING OF SUBSYSTEM IN HARD DISK DRIVE

Residual vibration is one of the primary mechanical problems that affect the dynamic characteristics of the head actuator assembly in hard disk drives, and the data access speed and positioning resolution. This paper presents the experimental modal testing and finite element modelling that are tailored to vibration testing in the head actuator assembly. The special excitation method has been applied for modal testing of the head actuator assembly, based on voice coil motor without altering the modal property of the structure in actual operating condition. The finite element models of the head actuator assembly have been developed, and various modes have been analysed. It is shown that the dynamic characteristics of the head actuator assembly are very complicated, in particular the vibration due to the lateral quasi-rigid body mode caused by the flexibility of the pivot, and mass and structure of the head actuator arm. It is thus essential to develop effective approaches to reduce the vibration of the lateral quasi-rigid mode and improve the dynamic characteristics of the head actuator assembly, so that high-performance HDD can be developed.     

汽车钢板弹簧的应力和变形分析

应用有限元法对一种在垂直力作用下的3片式钢板弹簧进行分析,其中应用8节点块单元对板簧进行实体建模,采用接触分析来模拟板簧各片逐渐进入接触的情况。对钢板弹簧的中心螺栓、U型螺栓夹紧和卷耳、吊耳部分的铰链约束进行独特的处理。应用所建立的有限元模型计算板簧的应力分布和载荷-变形曲线。对该板簧进行的实验应力分析表明,应用该有限元模型得到的计算应力和载荷-变形特性与试验结果吻合较好。     

产品抗冲击强度分析的有限元建模及落球冲击试验仿真

验证机电产品抗冲击强度的传统方法主要是通过冲击试验,然后检验是否被破坏来判断;而结构在受冲击载荷时所受力大小及其变形程度,根本无法从该试验中得到.应用MSC.Patran和rdSC.Dytran软件,在冲击载荷情况下对机电产品元件进行有限元建模,分析产品抗冲击性能,通过仿真对结构强度进行验证,可减少试验验证次数,提高设计质量.     

某雷达座结构的有限元分析及优化设计

在实现雷达功能的基础上,要求雷达座质量轻、刚度大,设计了一种雷达支撑座,并分析结构承受载荷情况.用有限元方法,对雷达座结构进行分析,得到雷达座的强度和变形情况,将某一节点的等效应力值与理论计算结果进行对比,验证了有限元仿真结果的可靠性.根据有限元分析结果,对雷达座进行结构改进.分析各构件尺寸对质量、最大应力和最大变形的...