微型燃气轮机向心透平的设计和研究

在研究微型燃气轮机向心透平结构特点和工作原理的基础上,建立了向心透平设计计算的数学模型.利用计算机辅助设计技术完成向心透平的热力计算和通流部分的结构设计,应用参数化设计思想和三维建模技术实现其变参数时的快速实体建模,应用有限元分析方法进行叶轮的结构分析和优化,基于虚拟操作平台实现其装配顺序规划、碰撞检测和装配仿真.     

电梯轿厢架轻量化的分析研究

以某型号电梯的轿厢架作为研究对象,利用现代的电梯设计方法,建立电梯轿厢架的有限元模型。在建立模型时融入了参数化建模和模块化建模的思想,减少了分析时前处理的时间。     

三维CAD技术在内燃机设计中的应用

本文通过大量实例，介绍了CAD技术在内燃机设计中的多项应用。从计算机辅助建模及计算机辅助分析两大模块入手，介绍了内燃机零部件三维建模技术、物性计算、参数化设计、CAM模拟装配以及有限元在强度分析中的应用等内容。     

DF4D型机车滚动抱轴箱裂损原因分析及改进

简述了DF4D型机车滚动抱轴装配的发展过程,对滚动抱轴箱的运用情况及裂损部位作了说明,对滚动抱轴箱作了简单的受力分析及有限元分析,从结构上对滚动抱轴箱的主要设计参数与相对成熟的8K、6K、SS6B等型机车的滚动抱轴箱进行对比。通过受力分析、有限元计算及结构对比,提出了既有DF4D型机车滚动抱轴箱改进的措施。     

发动机曲轴压入型橡胶扭转减振器鼓形与装配性能的优化

研究了压入型橡胶扭转减振器的鼓形设计方案和装配性能优化的方法。首先论述了压入型橡胶扭转减振器装配性能指标及其测试方法。基于有限元分析,计算了压入型橡胶扭转减振器装配性能指标,并与实测值进行对比验证。鼓形影响扭转减振器装配性能是一个多因素、多指标的试验问题,利用正交试验分析方法,对扭转减振器装配性能进行影响因素的分析。采用BP神经网络遗传算法,对压入型橡胶扭转减振器鼓形进行优化设计,将优化得到的结果和实测结果作对比分析,最大相对误差小于10%。     

有限元等效应力在拱坝体型优化设计中的应用

基于有限元计算软件ANSYS,结合工程实例,利用参数化设计语言APDL将拱坝等效应力应用于应力约束,进行拱坝体型优化设计.实例计算分析表明,该方法合理、有效.     

汽轮机槽型密封圈的理论计算方法

为了设计新型的槽型密封圈,以满足新机组中高参数、新结构的密封要求,需要通过理论模型分析槽型密封圈各个参数各自的作用及之间的相互关系。提出了一种基于悬臂梁模型的槽型密封圈的理论计算方法,成功推导了槽型密封圈的轴向刚度和密封应力的理论公式,并分析了槽型密封圈的密封机理。通过与有限元结果对比,验证了该理论计算方法的可行性和可靠性,为新型槽型密封圈的设计提供了重要依据。     

发动机曲轴齿轮过盈接触有限元分析研究

结合某发动机曲轴齿轮过盈装配的实际参数,建立了三维实体模型,采用有限元分析方法,对曲轴齿轮过盈装配进行计算分析,探讨了曲轴齿轮过盈装配时最大主应力、等效应力、接触压力等随过盈量的变化关系,为后续的曲轴齿轮过盈装配设计分析提供参考依据。     

汽轮机转子叶片模化与模态分析

采用Solidworks软件对国产某600MW汽轮机低压转子进行三维实体建模,针对汽轮机长叶片提出了一种叶片模化方法。基于Algor有限元软件对该型机组低压转子进行了模态分析,将临界转速计算结果与传统的圆盘法所得结果以及设计数据进行比较,比较结果表明:提出的叶片模化方法是可行的,运用该方法处理的叶片模型在理论上更接近实际叶片。研究结果为透平机转子的设计及其动力学有限元三维实体建模提供了一定的参考。     

某低速柴油机活塞冷却油管装配抗脱松力分析

某型船用低速柴油机活塞冷却油管在运行中发生脱落。为了研究不同装配尺寸对冷却油管装配抗脱松力的影响规律,采用有限元方法研究冷却油管与连接法兰过盈接触面接触压力分布情况,并通过与理论计算值的对比分析验证了有限元结果的合理性。然后通过理论计算得到装配尺寸对冷却油管抗脱松力的影响规律,从而指导活塞冷却油管与法兰面装配过盈量的合理设置。     

汽轮机叶片三维参数化特征造型研究

针对汽轮机叶片的结构特点,提出了叶片参数化建模的特征分类形式,采用CSG与B-rep共同构造了叶片的三维实体。然后利用这一技术开发了汽轮机叶片的参数化特征造型系统,其中采用Visual C 开发了良好的人机界面,并使用OpenGL图形技术进行叶片造型显示。以某汽轮机低压缸围带双倒T叶根扭叶片为例阐述了参数化特征造型的思路,并展示了该造型系统的一些功能。该三维参数化特征造型方法不仅可以应用于汽轮机叶片,也可以应用于其它一些典型结构件的参数化设计,为进一步进行有限元分析以及数控加工奠定基础。     

A numerical analysis of PEMFC stack assembly through a 3D finite element model

A finite element model is developed to investigate the influence of the assembly phase of proton exchange membrane fuel cell (PEMFC) stacks on the mechanical state of the active layer (MEAs). Validated by experimental measurements, this model offers the possibility to analyze the influence of different parameters through the use of a complete parametric set, such as the number of cells and their position in the stack. The simulations show that a better uniformity of the MEA compression is obtained with the greatest number of cells, and at the center of the stack. The finite element analysis (FEA) is finally found to be an effective tool to show the influence of the assembly phase on the performance of PEMFCs, and will help the designer to adapt the future generations of stack to ensure the uniformity of the MEA mechanical strain.     

大开孔补强的参数化分析设计

利用ANSYS的APDL语言对圆筒体中大开孔及其补强进行参数化分析设计,规范了有限元分析的过程,并使不具备有限元使用经验的普通用户,通过该程序轻松实现圆筒体开孔补强的分析设计.     

A prototype design model for deep low-enthalpy hydrothermal systems

This paper introduces a prototype design model for deep low-enthalpy hydrothermal systems. The model predicts, empirically, the lifetime of a hydrothermal system as a function of reservoir porosity, discharge rate, well spacing, average initial temperature of the reservoir, and injection temperature. The finite element method is utilized for this purpose. An extensive parametric analysis on a wide range of physical parameters and operational scenarios, for a typical geometry, has been conducted to derive the model. The proposed model can provide geothermal engineers and decision makers with a preliminary conjecture about the lifetime of a deep low-enthalpy hydrothermal system. The proposed modelling technique can be utilized as a base to derive elaborate models that include more parameters and operational scenarios.     

Parametric study on geometric and material properties of polymer electrolyte membrane fuel cell with free vibration analysis

The mechanical aspect of understanding the dynamic behaviour is very important in stack assembly of fuel cell configuration. Designing such configuration would be very useful to tune the system accordingly to avoid catastrophic failure due to resonance. The dynamic analysis of a polymer electrolyte membrane fuel cell (PEMFC) is performed to understand its response during complex loading nature. The stack assembly of bipolar plate, gas diffusion electrolyte (GDE) and membrane are modelled and analysed using Mindilin plate element with finite element method (FEM). The parametric study on thickness, density and young's modulus and its influence on dominant modes of natural frequencies are analysed with a 5%–20% range of variations. It is observed that the bipolar plate's thickness plays a vital role in the vibration behaviour of the PEMFC.     

基于参数化建模的转子有限元剖分

分析汽轮机转子的结构特点,将汽轮机转子结构参数化,提出了汽轮机转子参数化建模的方法,提高了转子原始几何模型的输入效率和准确性。利用有限元网格生成的Delaunay三角化方法,得到了汽轮机转了二维有限元计算模型,生成的有限元网格大小均匀,疏密过渡平滑,没有奇异单元,从而保证了转子温度场和热应力有限元分析计算的精度。     

3D coupled CFD/FEM modelling and experimental validation of a planar type air pre-heater used in SOFC technology

In this present paper, a coupled 3D thermo fluid-thermo mechanical modelling approach of a plate type air pre-heater is introduced. The conjugate heat transfer within the pre-heater is numerically solved using 3D computational fluid dynamics. The model considers the discrete structure of the whole pre-heater assembly including the air channels, plates and manifold ports. Wall surface and gas temperature measurements are performed using thermocouples to validate the numerically predicted calculations. The results show good agreement, implying that the proposed model can be used in the design and process optimisation of the air pre-heater. Moreover, a submodel created from the thermofluid analysis has been used to investigate the thermomechanical behaviour of the air pre-heater manifold region using the nonlinear finite element method. The nonlinear elastic-plastic behaviour of the material has been considered. The component locations susceptible to stress could be determined. The approach results in reduced prototype costs and product development time in the design and optimisation of efficient air pre-heater designs.     

Finite element analysis of shell and tube heat exchanger

A finite element model to predict temperature distribution in heat exchangers is reported. The model can be effectively used to analyse and design the heat exchangers with complex flow arrangements for which no regular design procedure is available. Illustrations are provided to explain the application of the method for the analysis of shell and tube heat exchangers.     

数值仿真技术在燃油泵托架疲劳损伤分析中的应用

论文针对某燃油泵托架出现异常断裂开焊的现象,利用UG、Hypermesh及Ansys软件建立了该燃油泵托架结构的有限元模型,并利用模态试验结果验证了模型的正确性。利用试验模态分析结果修正有限元模型的物理特征,确定了系统的阻尼和减振橡胶的刚度。为建立复杂装配结构的有限元模型及进行合理的结构动力学分析、疲劳寿命预测等工作提供了有价值的参考和依据。