Finite element analysis of shot-peening effect on fretting fatigue parameters

Shot peening is widely used to improve the fretting fatigue strength of critical surfaces. Fretting fatigue occurs in contacting parts that are subjected to fluctuating loads and sliding movements at the same time. This paper presents a sequential finite element simulation to investigate the shot peening effects on normal stress, shear stress, bulk stress and slip amplitude, which are considered to be the controlling parameters of fretting damage. The results demonstrated that among the modifications related to shot peening, compressive residual stress has a dominant effect on the fretting parameters.     

高速角接触球轴承接触疲劳寿命的有限元分析

首先简述了滚动轴承寿命的基本理论以及传统估算方法.然后根据轴承结构与工作特点,指出了滚动体与滚道的接触疲劳是轴承的主要失效形式,通过总结一般结构疲劳分析方法,提出了滚动轴承采用有限元法进行疲劳分析的方法和步骤.针对实际课题,对给定工况下的角接触球轴承B7005轴承接触疲劳寿命的有限元分析,将分析结果与轴承经典寿命估算结果进行了对比,一定程度上验证了提出的滚动轴承有限元疲劳分析法的合理性.     

Finite element modelling and experimental modal testing of a three-dimensional framework

The object of this paper is to develop a finite element model for a 1/10 scale crane rig in the laboratory, so that one may predict the dynamic behaviour of the scale crane rig based on the relevant features of the developed finite element model. To this end, the finite element modelling and experimental modal testing for the 1/10 scale crane rig are first carried out. Two kinds of coupling for the transducer and the tested structure for achieving the better experimental outcome are proposed. The finite element model is then modified, according to the experimental results, using various techniques. It has been found that the new modified finite element model, by replacing the conventional infinite rigidity for the ground-fixed nodes by the appropriate stiffness for the translational and rotational springs, can predict the vibration characteristics of the experimental crane rig with satisfactory accuracy.     

大型升船机船箱门静力与疲劳有限元分析

应用结构强度理论和疲劳设计原理，采用有限元方法对某大型升船机船箱门的静力与疲劳性能进行了分析。首先根据疲劳设计理论确定了计算中的若干参数，其次按照使用要求分析了各种工况，最后建立了弧型闸门的有限元模型，运用结构分析软件ANSYS对各种工况进行了数值模拟分析。计算结果表明，该弧型闸门在使用年限内，在疲劳和静力学强度方面能够满足使用要求。     

桥式起重机有限元分析和疲劳寿命研究

以某180 t×24.85 m冶金桥式起重机为对象,应用有限元分析软件Ansys研究桥架的变形和应力分布状态,并与现场测试结果进行对比分析。结果表明,该起重机的最大挠度、静态Von Mises等效应力和第一阶固有频率均符合起重机设计规范要求。通过无损探伤发现桥架北主梁的下盖板上有裂纹,应用有限元分析和损伤容限设计对起重机裂纹的疲劳寿命进行研究,其分析数据可为起重机的日常维护检修和安全评估提供参考。     

刀具温度场的有限元分析

建立了正交切削的热传导分析模型,采用有限元法中的Lagrange法研究刀具的温度场,并分析刀具前角、进给量 对切削温度的影响规律,为研究刀具磨损机理、提高刀具寿命提供有用的参考数据。     

高温工况阀用波纹管疲劳寿命有限元分析及试验研究

对于某些特殊应用领域的阀用波纹管,用户有对波纹管在高温工况下进行疲劳寿命型式试验的需求.由于该实验装置专业性较强,目前国内市场上暂无该类产品的销售.为了解决此问题,设计了一种高温工况下使用的疲劳试验装置,该装置能够在不同温度、不同压力条件下对波纹管进行疲劳试验.由于在高温疲劳试验过程中存在试验效率低、较常温试验条件增加...     

Finite element simulations of static and sliding contact between a human fingertip and textured surfaces

This paper presents a mechanics study of the variations with position and time of stresses within the dermis and epidermis of a human fingertip when it is loaded and slid over textured surfaces. Its purpose is to examine how fingerprints interact with surface texture to cause stress variations in tune with the sensitivities of Meissner and Pacinian corpuscles through which humans in part interpret tactile sensations. A two-dimensional multilayer elastic finite element model of a fingertip has been created for this purpose. Results show that fingertip’s epidermal ridges have little effect on stress distribution within the fingertip in static loading but significantly increase stress oscillations during sliding over a textured surface. Oscillation frequencies from the sliding simulations are in ranges that should stimulate a fingertip’s Meissner and Pacinian corpuscle nerve endings.     

塔架结构的静动态特性有限元分析

通过对某架空索道塔架的静、动态分析,探讨如何在ANSYS中利用梁单元建立塔架有限元模型的问题及计算方法,并利用ANSYS程序对该塔架进行静、动态分析计算,计算结果与试验数据吻合。     

渐开线直齿圆柱齿轮齿根应力的有限元分析

根据啮合原理 ,建立了轮齿齿廓的精确模型。在此基础上 ,建立了整个齿轮平面有限元模型 ,并进行了分析计算。根据计算结果总结出了在对轮齿齿根应力进行有限元分析时 ,模型参数的选取原则 ,并对在该原则下建立的二维和三维模型分别进行了计算 ,将各种模型下的计算结果进行了比较 ,证明了所述原则的有效性     

矿用隔爆变压器箱体的有限元计算与分析

采用三维设计软件建立变压器箱体模型，并对三维模型进行有限元分析计算，显示变压器箱体受力后变形情况，最大应力值和位移值，箱体上任一单元的应力、位移值，比较是验证计算结果的正确性，为变压器箱体的设计和优化提供了科学依据。     

A coupled finite element and meshfree analysis of erosive wear

Erosive wear is a kind of material degradation, which is largely involved in many industries, and caused a series of serious problems and economic loss. Many theoretical models and numerical models have been established to study the erosion phenomena. In this study, a coupled finite element and meshfree model was developed for the simulation and prediction of erosive wear. By utilizing the meshfree technique, the error due to mesh distortion and tangling at impacted area in the finite element analysis could be effectively avoided. The fundamental mechanisms of erosion by solid particle impact were investigated as well. Comparison against the results of analytical erosion models and finite element model are made. It is shown that the predicted results are in agreement with reported results. The present study could be very useful and efficient in studying erosive wear.     

Hybrid radial basis function/finite element modelling of journal bearing

This paper presents a novel approach through the combination of radial basis function (RBF) with Galerkin finite element method (FEM), to determine the solution of journal bearings. We divide the flow field into several subdomains. Local weak integration form of Reynolds equation is developed. The new model uses the point interpolation based on RBF to obtain the shape functions in each subdomain. The global solution is set up on the base of the local solutions of each subdomain. We demonstrate the efficiency and accuracy of the new method in detail using a statically loaded bearing example and by numerical comparisons among RBF method, FEM method and the hybrid method. We found that the large node and element number problem, the large matrix condition number problem, and the shape parameter-sensitivity problem all decrease. We also simulate the self-excited instability phenomenon and unbalance response of a flexible rotor-bearing system with the new model successfully.     

空压机系统冲击动力特性有限元分析

构造船用空气压缩机系统各零、部件及整机的实体模型,建立系统的冲击动力分析有限元模型。应用I DEAS软 件计算了空压机系统的固有特性、约束模态和冲击动态响应,给出各自由度方向加速度冲击载荷作用时系统的振动响应 及动态应力,为确定船用空压机的抗冲击能力及减振装置的合理设计提供了理论依据。     

整体弹性关节平面并联微动机器人ANSYS有限元分析

对整体弹性关节平面并联机器人建立刚性模型,采用闭环线型原理建立理论运动学线性模型(Jacobian矩阵),然后用ANSYS软件对其进行有限元分析,得到有限元运动学模型(Jacobian矩阵值),最后讨论两者关系,发现有限元模型比理论模型要精确.     

Finite element modeling of residual stresses in machining induced by cutting using a tool with finite edge radius

A thermal elastic-viscoplastic finite element model is used to evaluate the residual stresses remaining in a machined component. An improvement in the accuracy of the predicted residual stresses is obtained by: (a) using a modified Johnson–Cook material model that is augmented by a linearly elastic component to describe the material behavior as non-Newtonian fluid; (b) using a remeshing scheme to simulate the material flow in the vicinity of the rounded cutting tool edge without the use of a separation criterion; (c) properly accounting for the unloading path, and (d) considering the thermomechanical coupling effect on deformation. Case studies are performed to study the influence of sequential cuts, cutting conditions, etc., on the residual stresses induced by orthogonal machining.     

基于MW级风力发电机塔架的有限元分析

讨论了MW级风力机塔架的有限元静力及稳定性建模分析和有限单元类型的选取及计算方法,并以1.5MW某风力发电机塔架为例,对风力发电机塔架结构进行了静力分析和稳定性分析.得出塔的截面按照变截面来进行设计是合理的,分段式塔架是一种合理的结构,各段塔架所受应力不等;塔架稳定性取决于其一阶屈曲临界载荷,荷载作用下塔架的应力最大处并不一定就是其屈曲薄弱点,而应力较大且挠度较大的薄壁部位,是发生屈曲失稳的危险点.     

大型原油储罐的有限元分析

10万m3储罐在原油储备中应用越来越广泛,其强度安全要求显得更重要。通过有限元软件ANSYS,对水压试验工况下的10万m3大型外浮顶式原油储罐进行了分析,获得了储罐各部位的应力分布情况,用分析设计标准对主要部位进行了应力评定并确定了关键部位,强度评定的结果表明,在最高液位下储罐可以安全运行,不会发生强度不足失效。     

700t单门式桅杆横梁吊装设备有限元计算

用有限元法对石油化工生产中７００ｔ级反应器吊装用新型单门式桅杆横梁吊装设备进行强度、刚度计算分析,并依据计算结论,对吊装设备的结构进行加强和优化。计算结果实践证明,该新型单门式桅杆横梁吊装设备的结构设计合理,力学性能好,强度、刚度满足设计和吊装要求。     

汽车轴类零件非均匀材质力学特性的有限元分析(Ⅱ)

采用有限元方法模拟了汽车轴类零件非均匀材质力学特性。对汽车轴类零件常见非均匀材质特征进行了分析,建立了轴类零件的有限元模型,并采用统计技术确定不同单元的材料属性以反映材料的非均匀性。通过数值迭代,研究了材料非均匀性对材料最大应力与疲劳寿命的影响,对于工程设计具有一定的参考意义。