发动机活塞温度场试验与有限元分析

依据发动机活塞的热负荷,介绍热电偶法测量活塞温度的试验方法和过程,建立活塞有限元模型,分析热边界条件的施加方法。计算结果与试验结果很好地拟合,为发动机活塞的耦合分析和结构优化提供了可靠依据。     

发动机活塞光弹应力试验与有限元分析

依据发动机活塞的机械负荷,介绍了活塞光弹应力试验的模型制造和试验过程,建立了活塞有限元模型,分析了机械边界条件的施加方法.计算与试验结果很好地吻合,为发动机活塞的耦合分析和结构优化提供了可靠依据.     

基于有限元方法的柴油机活塞热分析

介绍运用有限元方法对柴油机机活塞进行热分析的方法。具体针对某型号柴油机,分析其活塞稳态温度场和热变形。分析结果表明,活塞最高温度出现在活塞头部,为377.22℃;活塞轮廓的径向变形最大值为0.451mm,也发生在活塞头部。并对活塞热态纵向型线进行拟合,为活塞冷态纵向型线的设计提供参考依据。     

A study of a two-stroke free piston linear engine using numerical analysis

We studied a two-stroke free piston linear engine by numerical models and simulation. The numerical models consisted of three parts: dynamic model, linear alternator model, and thermodynamic model. These models were combined and solved by a program written in Fortran. To validate the numerical models, simulation results were compared with experimental data at the same initial conditions. To provide information for the study, the effects of key parameters such as equivalence ratio, reciprocating mass, spark timing, and spring stiffness on the operating characteristics as well as performance of the engine were investigated. The simulation results indicated that by using numerical models as mentioned, the calculation data were closely similar to experimental data. Besides, this engine showed a great benefit for dynamic of piston, electric power output, and performance as spark timing was adjusted near the cylinder head. By decreasing reciprocating mass and increasing spring stiffness, the piston dynamics as well as electric power output of the engine was also improved significantly. In addition, high engine performance could be easily obtained by optimizing the key parameters.     

Multi-domain structural-acoustic coupling analysis using the finite element and boundary element techniques

A new approach to analyze the multi-domain acoustic system divided and enclosed by flexible structures is presented in this paper. The boundary element formulation of the Helmholtz integral equation is used for the internal fields and the finite element formulation for the structures surrounding the fields. We developed a numerical analysis program for the structural-acoustic coupling problems of the multi-domain system, in which boundary conditions such as the continuity of normal particle velocity and sound pressure in the structural interfaces between Field 1 and Field 2 are not needed. The validity of the numerical analysis program is verified by comparing the numerical results with the experimental ones. Example problems are included to investigate the characteristics of the coupled multi-domain system.     

发动机活塞组的耦合有限元分析

利用Pro/E软件建立了某涡轮增压发动机活塞组的三维实体模型.通过有限元软件Hv-perMesh和ANSYS,分别完成了活塞组在机械负荷、热负荷和热力耦合作用下的有限元分析,得到了活塞的应力和变形情况,为活塞的结构改进及优化设计提供理论依据.     

柴油机活塞有限元分析与结构改进

活塞是发动机中工作情况最为恶劣的零部件之一.对495柴油机活塞的温度、热应力及变形、机械应力及变形进行了分析,并给出了活塞的热、机械耦合应力与变形,针对分析结果指出了活塞结构的改进方向.该分析可为类似发动机活塞的分析与结构改进提供理论参考与实践指导.     

汽油机活塞的有限元分析与优化

利用UG软件的相关参数化设计方法和用户定义特征建立活塞连杆组件的参数化模型。计算活塞所承受的载荷,采用UG NX软件中的Structure模块进行有限元分析与优化,优化器选择Altair的HyperOpt。以减轻质量为目标,快速方便地完成活塞的有限元分析与优化。     

基于UG的空压机活塞设计及有限元分析

活塞是空气压缩机的核心部件,其设计的合理性及可靠性关乎整机的质量.本文对活塞工作原理进行了初步分析,明确了结构设计方案.在设计过程中,充分利用UG参数化设计模块及有限元分析模块,对活塞的应力及位移进行了动态仿真.通过计算分析,验证了活塞的安全性.基于有限元法的参数化设计为今后活塞改进提供了重要依据.     

基于质量限制的全钢活塞三维有限元分析

为满足发动机向高功率密度(HPD)方向发展的需要,设计了一种新型全钢活塞,利用有限元软件MSC.NASTRAN对其进行热负荷、机械负荷以及热负荷和机械负荷共同作用下的分析计算,并与传统铝活塞在重量上进行了对比,为全钢活塞的结构分析和改进提供了参考。     

Sound radiation from strip plates with longitudinal stiffeners using waveguide finite and boundary element methods

In this study, the vibration characteristics and sound radiation of strip plates with finite width and infinite length are investigated numerically in order to analyze the vibration and sound radiation of structures consisting of many stiffened and double-layered plates. The waveguide finite element approach, which is effective for waveguide structures, is applied as a numerical scheme. The sound power and radiation efficiencies for an unstiffened plate are calculated numerically via coupling boundary elements to the WFEs. Longitudinal stiffeners and additional upper plates are included in the plate model to investigate the effect of stiffeners and an upper plate on sound power and radiation efficiency. In this study, it is found that the stiffeners contribute differently to plate vibration and sound radiation, and that the radiation efficiencies of the stiffened and double plates are larger than those of the unstiffened plate due to the presence of the stiffeners.     

发动机陶瓷隔热层性能的有限元分析

本文应用Ansys软件模仿发动机气缸套,对陶瓷内衬涂层的隔热部件的传热性能进行了有限元分析,并运用序贯耦合方法计算了陶瓷层与基体的热应力.     

大型钢结构件有限元力学分析方法研究

大型钢结构件有其独特的结构特点和载荷特点,在对其进行有限元力学分析时也有其相应的方法和特点,但目前具体介绍大型钢结构有限元力学分析方法和技巧的资料几乎没有。结合工程实际,对基于ANSYS软件的大型钢结构件的结构及载荷特点、有限元建模及其力学分析方法进行了研究,为该类结构件有限元力学分析提供借鉴。     

新型二冲程微型摆式内燃机中心摆温度场的有限元分析

在新型二冲程微型摆式内燃机(MFSPE)的设讦及完善过程中,温度场分析占有重要地位。从数值计算所得的燃烧室周期温度曲线中,均匀提取32个载荷点,基于ANSYS软件按32个载荷步进行载荷施加及求解分析,得出了中心摆各载荷步的温度场等效云图,并对部分有代表性的图从温度场的角度进行分析,提出了中心摆改进设计建议。     

基于参数化有限元模型的活塞热负荷仿真分析

应用COSMOS／M参数化有限元程序语言及Delphi面向对象高级语言,建立了490型柴油机活塞的参数化三维有限元计算分析模型及其数据输入输出处理接口,对活塞温度场及其影响因素进行了定量分析,并在此基础上,对490型柴油机虚拟故障工况下的热负荷进行了模拟计算,为故障仿真提供一种方便高效的手段。     

大型船闸活塞杆表面检测机器人的设计及有限元分析

针对大型船闸活塞杆表面检测的恶劣环境,设计一种自动化的检测机器人.通过主体电推杆来实现沿着活塞杆表面的攀爬动作;通过磁力吸附步进装置,实现对活塞杆表面的吸附、松弛;通过直流编码电机控制检测装置位于活塞杆表面的不同方位,从而获取活塞杆表面二维信息图.有限元分析结果表明:磁力步进吸附装置能够实现对活塞杆表面的吸附,检测装置...     

箔式应变片结构模型与有限元分析

长期以来，人们一直关心应变片的应变传递机理，以及应变片各组成部分对其性能的影响。Larry Burrow用有限元方法对应变片结构模型进行了分析，并分析了应变片系统中各组成元件对其性能的影响。     

发动机活塞的热结构耦合分析

用ANSYS计算了该发动机活塞二维轴对称简化模型单独在燃气压力和燃气温度作用下以及在燃气压力和温度共同作用下的温度分布、应力和位移,并且计算了活塞三维1/4模型的温度场;最后对计算结果进行了全面的综合比较分析.     

箔式应变片结构模型与有限元分析

长期以来，人们一直关心应变片的应变传递机理，以及应变片各组成部分对其性能的影响。Larry Burrow用有限元方法对应变片结构模型进行了分析，并分析了应变片系统中各组成元件对其性能的影响。     

Acoustic analysis of lightweight auto-body based on finite element method and boundary element method

A lightweight automotive prototype using alternative materials and gauge thickness is studied by a numerical method. The noise, vibration, and harshness (NVH) performance is the main target of this study. In the range of 1–150 Hz, the frequency response function (FRF) of the body structure is calculated by a finite element method (FEM) to get the dynamic behavior of the auto-body structure. The pressure response of the interior acoustic domain is solved by a boundary element method (BEM). To find the most contributing panel to the inner sound pressure, the panel acoustic contribution analysis (PACA) is performed. Finally, the most contributing panel is located and the resulting structural optimization is found to be more efficient. __________ Translated from Journal of Shanghai Jiaotong University, 2006, 40(1): 177–180 [译自: 上海交通大学学报]