查询词典 fem

The nitriding process of a large-scale crank shaft made from 35CrMo steel is simulated using non-linear FEM for the different supporting situations based on the above-stated visco-elastic mathematical model and measured data.

由于大型曲轴形状非常复杂，本文针对四种不同的支撑方式，用三维非线性有限元法结合上述粘弹性数学模型和实测数据模拟计算了35CrMo大型曲轴气体渗氮过程变形情况。

With the development of FEM theory and simulating software, FEM softwares simulation to gravity dam has great engineering signality and practical value.

随着有限元理论的完善和仿真软件的不断发展，采用有限元软件对重力坝进行仿真模拟具有重要的工程意义和实用价值。

3D-CTM (Coupled Thermo-Mechanical Forming Simulation) software for precision forging process of aero-engine blade was developed. The key technologies of 3D coupled rigid-viscoplastic thermo-mechanical FEM simulation of blade forging process were studied systematically. By using the remeshing method of contracting from the boundary to the inner, new mesh system from old distorted mesh system can be obtained. A method of modifying the position of nodes touching on the die according to its original normal was proposed to avoid "dead lock" problem due to uncontinuity of normal of scatted die meshes. The pseudo-static iterative algorithm was used to simplify the coupled thermo-mechanical computation. In particular, formulations to determine relaxation factor β was established for rigid viscoplastic FEM adopting penalty function method, and an improved cubic factor rapid algorithm derived from these formulations was proposed by combining with the advantage of advance and retreat search method.

采用基于边界构形的内缩法，实现了三维畸变网格的重新划分；提出了初矢修正法对触模节点的位置进行修正，解决了由于离散的模具网格的法矢不连续造成的&死锁&问题；采用准静态迭代法简化了速度场和温度场耦合计算过程；特别是针对减速因子β的选取，建立了适用于三维复杂成形过程刚粘塑性罚函数法有限元三次因子法的计算公式，并结合进退搜索法提出了改进的三次因子快速算法，提高了模拟计算效率和稳定性，在此基础之上，开发了面向叶片精锻过程的三维刚粘塑性热力耦合有限元模拟分析系统(3D-CTM)，系统的可靠性得到了圆柱体镦粗的验证。

By dynamic stability analysis and calculation in means of FEM, the three-dimension data processing technique for arbitrary cross sections of solid masses was adopted, then the safety factor of the abutment of arch dam was provided using FEM, and corresponding programs was compiled.

采用有限元法进行动力分析计算，利用三维实体任意切面数据处理技术，提出了应用有限元法计算拱坝坝肩稳定安全系数方法，在此基础上完成了基于有限元法以坝肩动力稳定安全系数为目标的高拱坝优化设计程序。

After verification of FEM, 45 species of 15 series are computed. The major parameters including slippage coefficients, pretensions forces, dimensions of angles, arrangement of bolts, connection method among angle, beam web, column flange, and so on are studied. Some important conclusions are drawn.At last, Advices for seismic design based on tests and FEM analysis are presented at last. The study is rather comprehensive and systematic, and the conclusions. can be useful for revising design code, guiding design of engineering, and provide good basis for further to study behavior of shear beam-to-column connections.

主要研究了摩擦系数、螺栓预拉力、螺栓线到与柱连接角钢肢背的距离、螺栓直径及级别、梁长、螺栓排列布置、梁高、柱翼缘厚度、角钢厚度、角钢长度、梁腹板只与角钢肢尖相焊接、钢材强度、角钢与梁柱均栓接、角钢与柱焊接与梁栓接、角钢与梁柱均焊接等参数对腹板双角钢梁柱连接滞回性能的影响，得出了一系列重要的结论。

In this dissertation, based on the systematically analysis of theory and application research on deformable model, a new B-spline active contour based on the finite element method is proposed; then B-spline active contour is applied to fitting the digital curve cross-sectional contour, and adaptive FEM is adopted to improve the precision; lastly the model is generalized to 3D, and a B-spline active surface model based on FEM is proposed.

本文在系统地分析了国内外关于可变形模型理论与应用研究的基础上，提出了一种基于有限元法的B样条主动轮廓模型；并将其应用于由断层图像导出的截面轮廓数字曲线的拟合，利用自适应有限元技术提高拟合精度；最后将其推广到三维，提出了基于有限元法的B样条主动曲面模型。

Combined hourglass control in analysis of cold ring rolling process;2. Recent status and development of real-time measurement and online control technology in cold ring rolling ;3. The influence law of feed rate of idle roll on the quality of end face of ring,axial width spread ratio,roll force,roll moment and metal flow characteristic in cold ring rolling process has been explored through the FEM numerical simulation of the ring with rectangular cross-section based on the elastic-plastic dynamic explicit FEM under the Abaqus software environment.

基于Abaqus/Explicit提供的显式动力学有限元算法，对矩形截面环件冷辗扩进行了有限元数值模拟，揭示了芯辊进给速度对环件冷辗扩过程中环件端面质量、轴向宽展率、辗扩力、辗扩力矩以及金属流动特性的影响规律，并从金属塑性成形原理和塑性加工力学等角度对这些规律进行了合理的解释，从而获得了进给速度对冷辗扩成形的影响规律，为环件冷辗扩在实际应用中进给速度的选择提供了依据，对揭示冷辗扩成形机理也具有十分重要的意义。

The influence law of feed rate of idle roll on the quality of end face of ring,axial width spread ratio,roll force,roll moment and metal flow characteristic in cold ring rolling process has been explored through the FEM numerical simulation of the ring with rectangular cross-section based on the elastic-plastic dynamic explicit FEM under the Abaqus software environment.

基于Abaqus/Explicit提供的显式动力学有限元算法，对矩形截面环件冷辗扩进行了有限元数值模拟，揭示了芯辊进给速度对环件冷辗扩过程中环件端面质量、轴向宽展率、辗扩力、辗扩力矩以及金属流动特性的影响规律，并从金属塑性成形原理和塑性加工力学等角度对这些规律进行了合理的解释，从而获得了进给速度对冷辗扩成形的影响规律，为环件冷辗扩在实际应用中进给速度的选择提供了依据，对揭示冷辗扩成形机理也具有十分重要的意义。

The major content of this thesis are as follows:1 Performed FEM analysis before strengthening, and to find out the reason for the cracking and present a strengthening scheme;2 Performed nonlinear FEM analysis before and after strengthening, and to get the varying rule of the relative displacement between the on-site cast concrete side wall and that between the precast concrete arch and the floor, as well as the stress distribution of the gallery;3 Performed on-site observation experiments on the 7~th gallery, and to get the varying rule of the relative displacement between the on-site cast concrete side wall, as well as that between the precast concrete arch and the floor.4 The results of the computation were compared with those of experiments, which verified the effect of the strengthening.

本文的主要工作有： 1 对加固之前的廊道结构进行有限元计算，找出廊道底板开裂的原因，提出加固方案； 2 对加固前后廊道结构进行非线性有限元计算，得到加固前后廊道两现浇边墙相对位移、拱顶与底板相对位移随水库水位变化的规律和廊道结构的应力分布情况； 3 进行廊道加固前后现场观测试验，得到廊道两现浇边墙相对位移以及拱顶与底板相对位移随水库水位变化的规律； 4 对比分析加固前后现场观测试验与非线性有限元计算所得结果，论证加固方案的合理性，验证加固效果。

Using fluid dynamics FEM (two dimensional, three dimensional andaxisymmetric) and three dimensional acoustic FEM in meticulous analysis ofexpansion muffler structure, this paper studies the influences of each mufflercomponents' position, dimension, form and quantity on the fluid dynamic andacoustic performances;therefore the paper indicates that the end of the intruding tubeis the linchpin of the fluid dynamic performance of the whole muffler structure, thespringhead of muffler fluid dynamic performance is the smoothness of air current, themain factor which affects the acoustic attenuation value of expansion chamber muffleris the grade of saltation of the section of air conducting access, and the attenuationvalue of specific frequency can be dramatically enhanced by carefully designing thelength of expansion chamber.

本文通过流体力学有限元方法和三维声学有限元方法对扩张腔消声结构的参数化模型进行了细致的分析，研究了这种结构的各个组成部份的位置、大小、形状和数量对其流体力学与声学性能的影响，指出插入管端口是影响整个结构流体力学性能的关键，消声结构流体力学性能的根源是气流通过时的平稳程度；影响扩张腔消声量的主要因素为声波传播通路截面突变的程度，并可以通过精细的设计扩张腔轴向长度获得宽频或指定频率消声量的大幅度提高。

Lugalbanda was a god and shepherd king of Uruk where he was worshipped for over a thousand years.

Lugalbanda 是神和被崇拜了一千年多 Uruk古埃及喜克索王朝国王。

I am coming just now,' and went on perfuming himself with Hunut, then he came and sat.

我来只是现在，'歼灭战perfuming自己与胡努特，那麼，他来到和SAT 。