共查询到20条相似文献,搜索用时 63 毫秒
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文中利用弹性力学原理,通过阀片应力与阀片变形之间关系,创建了节流阀片应力系数和应力解析计算式.利用该应力计算方法.通过实例,对阀片的径向应力、周向应力和复合应力进行了解析计算和计算机仿真,与其它应力计算方法进行了比较和验证,并对计算偏差进行了分析.结果表明,节流阀片应力系数解析计算方法是准确的,不仅可以阀片在任意半径位置处的应力进行解析计算,还可以对阀片应力进行计算机仿真. 相似文献
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从齿轮加工原理出发,利用渐开线和齿根过渡曲线方程生成轮齿的精确齿形,建立2种等效直齿锥齿轮三维轮齿几何模型,研究渐开线直齿锥齿轮的精确建模方法.分别使用h-单元和p-单元分析计算直齿锥齿轮齿根应力,建立直齿锥齿轮三维轮齿齿根应力有限元计算模型和计算基准.计算结果与ISO国标公式比较,证明模型的正确性、精确性和可靠性. 相似文献
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传统采煤机齿轮啮合力应力计算方法存在齿轮啮合数据采集不准、传感器效率偏低问题,导致方法应用误差较大.针对上述问题,提出基于非分散红外(Non-Dispersive InfraRed,NDIR)技术原理的采煤机齿轮啮合力应力计算方法.利用NDIR气体传感器,实时采集采煤机齿轮啮合力应力数据,引入有限元方法构建模型,根据Hertz接触法实现静力等效分析以及静态接触分析,通过ANSUS/LS-DYNA计算采煤机齿轮啮合力应力.为验证研究方法的有效性,设计仿真.仿真结果证明了研究方法具有更小应用误差,拟合度较高,且成本较低,具有较好的应用前景. 相似文献
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基于组合杂交变分原理的4节点轴对称元 总被引:3,自引:1,他引:2
本文基于组合杂交变分原理推导四节点的轴对称元,依据能量协调条件,导出含有8个参数的轴对称应力模式.其优越性能突出表现在离散模型对于计算背景(如单元畸变和材料的不可压缩性等)的广泛适应性.数值算倒结果表明,该轴对称元位移和应力明显优于其它的轴对称元. 相似文献
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应用光弹性原理和方法,根据相似原理,对研究对象的几何尺寸进行缩比、模型设计及加工成型。将模型在危险载荷作用下,进行应力冻结、切片及应力分析。确定了模型不同截面上的应力及其变化规律,为优化设计和调整数值计算方法提供了有价值的依据。 相似文献
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1LS-DYNA中计算应力初始化有哪些方法?初始化应力计算在动力学问题求解中有较广泛的应用,例如重力载荷的初始化,旋转零部件离心预应力的施加,螺栓预紧力的施加等.初始化应力的合理处理能够使得动力学工况的计算结果最大程度地接近实际情况,所以应力初始化的处理显得较为重要.在擅长动力学计算的LS DYNA中,解决应力初始化有以下几种方法. 相似文献
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人体测量学并不是现代社会的产物。有着很长发展历史的人体比例理论中就包含了现代人体测量学的基本内容,尽管其还不够系统完整,但至少说明了在艺术创作中诞生的人体比例理论对现代人体测量学的影响。并随着时间的推移而不断的完善发展,为现代人体测量学的系统提出奠定了坚实的基础。 相似文献
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目的:解决在FLASH中导入声音的问题.方法:对FLASH不支持的声音格式采取音频压缩的方法.结果:可成功将压缩后的声音文件导入到FLASH中.结论:在FLASH中使用声音可以使FLASH动画具有良好的动画效果. 相似文献
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本文对于金属切削这一生产过程中所出现的不稳定问题,利用频率特性法中的奈氏判据,对其进行分析,从而找出消除自激振荡和达到切削过程绝对稳定的条件 相似文献
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David Smith 《AI & Society》2003,17(1):1-11
The paper questions the ability of current university systems to respond appropriately to the complex demands of an Information
Economy. It argues that new relationships between creative subjects and technology require new thinking about the nature and
purpose of universities per se. In particular, attention is drawn to the growing involvement of the private sector in higher
education. It is argued that it may not be appropriate to think of the `university of the future' in terms of current public
sector and quasi public sector institutions, but rather in terms of an emporium, based on an international trade in educational
services, and with the `University' as we now understand it occupying the functions of licensing, quality assurance and cultural
custodianship.
Accepted: 25 June 2002 相似文献
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All titanium alloys are highly reactive in the molten condition and so are usually melted in a water-cooled copper crucible to avoid contamination using processes such as Induction Skull Melting (ISM). These provide only limited superheat which, coupled with the surface turbulence inherent in most conventional mould filling processes, results in entrainment defects such as bubbles in the castings. To overcome these problems, a novel tilt-casting process has been developed in which the mould is attached directly to the ISM crucible holding the melt and the two are then rotated together to achieve a tranquil transfer of the metal into the mould. From the modelling point of view, this process involves complex three-phase flow, heat transfer and solidification. In this paper, the development of a numerical model of the tilt-casting process is presented featuring several novel algorithm developments introduced into a general CFD package (PHYSICA) to model the complex dynamic interaction of the liquid metal and melting atmosphere. These developments relate to the front tracking and heat transfer representations and to a casting-specific adaptation of the turbulence model to account for an advancing solid front. Calculations have been performed for a 0.4 m long turbine blade cast in a titanium aluminide alloy using different mould designs. It is shown that the feeder/basin configuration has a crucial influence on the casting quality. The computational results are validated against actual castings and are used to support an experimental programme. Although fluid flow and heat transfer are inseparable in a casting, the emphasis in this paper will be on the fluid dynamics of mould filling and its influence on cast quality rather than heat transfer and solidification which has been reported elsewhere. 相似文献
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熊林 《数字社区&智能家居》2007,3(14):428-429
虚拟化技术是当今服务器技术的一个主流方向,也是一项在计算机领域具有革命性意义的技术.作为x86架构体系下虚拟化技术的领军者-VMware,在技术上有其独到之处.研究VMware的技术与应用,对探知其优秀的技术特点,了解其成熟的产品体系有着现实意义. 相似文献
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杨革 《数字社区&智能家居》2006,(5):208-209
每一种媒体部有自身的长处,对某种特定的教学和学习有效。同样,每种媒体又不可避免地存在局限性,不利于某些教学和学习。因此,多媒体不是一种全能的媒体,也不可能代替传统媒体。现代媒体与传统媒体在教学中应相互补充,取长补短,相得益彰。 相似文献
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从品牌战略管理的高度出发,阐述了品牌传播符号语意的重要作用、常用方法以及要注意的问题,并以哈雷摩托为例进行了分析。 相似文献