查询词典 geometric boundary condition

The seal of car door is a complicated object, which has many special performances such as material nonlinearity, geometric nonlinearity and nonlinearity of boundary condition.

轿车车门密封条是一种复杂的材料非线性、几何非线性、边界非线性的特殊对象。

For a given geometric parameter there exists a boundary condition, which gives a minimum value of the total exergy loss rate for a unit volume, and vice versa.

该结论对优化设计换热器及对给定边界条件的换热器优化选取具有一定的指导意义。

The simulated results show that a stable acoustic standing wave is formed in bubble column under the geometric arrangements and the transducer boundary condition employed in this study. Due to the nonlinear behavior of the resonant wave and viscosity of water, there is a temporal shift at pressure nodes.

模拟结果表明，在本研究所用的几何布置和换能器与时间相关的速度入口边界条件下，反应器中形成了一个稳定的驻波声场；由于波的非线性以及水的粘性，压力波节点呈现出轻微的时间漂移性。

Based on analysis of the factors affecting subgrade local scour along the river such as condition of stream,condition of bed form,geometric boundary condition of river,water depth and speed of every section,scour depth of parapet,the progress of scour and the form of stream near parapet were observed through the way of field model experiment.

在对沿河路基局部冲刷影响因素如水流条件、河床沙条件和河流几何边界条件等进行分析的基础上，通过野外模型试验，观测了河流各断面的水深、流速、护墙的冲刷深度和冲刷的发展过程及护墙附近的水流形态。

Secondly, the construction simulation were performed by the model in ANSYS. The effect were emphasized in the construction process, which induced by temperature, geometric nonlinearity, and boundary condition. The conclusions were given that the stress decreased thirty percent for temperature change 10℃, and decreased fifteen percent for considering the elasticity support.

基于单元生死法施工模拟原理，运用ANSYS有限元软件建立了体育馆屋盖模型，进行了施工过程数值模拟，重点探讨了温度效应、几何非线性及支承条件对结构受力性能的影响规律，同时指出支承柱临界截面的存在，温度效应和边界条件变化对网壳结构边桁架杆件受力影响最为显著，温度变化10℃影响达30%，考虑支承弹性的影响在15%以上。

RCS of facetsof targets coated RAM was resolved by combining Impedance Boundary Condition and Geometric Optics and RCS of those edges were approximated by computing the RCS of edges of impedance wedge through Method of Equivalent Currents.

其中，涂覆目标面元的散射场是通过结合阻抗边界条件和几何光学法而得到；而涂覆目标棱边的散射场则是通过等效电磁流法求解阻抗劈的边缘绕射场近似得到的。

RCS of facets of targets coated RAM was resolved by combining Impedance Boundary Condition and Geometric Optics and RCS of those edges were approximated by computing the RCS of edges of impedance wedge through Method of Equivalent Currents.

其中，涂覆目标面元的散射场是通过结合阻抗边界条件和几何光学法而得到；而涂覆目标棱边的散射场则是通过等效电磁流法求解阻抗劈的边缘绕射场近似得到的。

In evaluation of errors of precise capacitor s due to geometric, imperfection, one has to solve Laplace equation subject to irregular boundary condition.

在研究精密电容器的几何尺寸误差引起的电容量误差时，往往需在不规则边界的边值条件下求解拉普拉斯方程。

Thirdly, according to the development of the frozen soil, the coupling model of single freezing pipe of axial symmetry of temperature field, stress field and moisture migration is put forward firstly. Then, by means of the progressing principle of potential field, the coupling model of temperature field, stress field and moisture migration which is under the condition of the multi-freezing pipes is extended. At last, the energy balance equation, stress balance equation, quality balance equation, geometric equation, physical equation, initial and boundary conditions etc are adopted to give the analytic solution to the problem of plane axial symmetry of single freezing pipe.

第三，在对室内试验和现场实测结果研究的基础上，分析了土体冻结过程中温度场、应力场、水分场耦合原理，并按照冻土体形成发展过程，首先建立了单一冷源冻结轴对称温度、应力、水分场耦合模型；接着利用势场的迭加原理，将单一冷源情况的三场耦合问题推广到多冷源情况的三场耦合；最后根据能量守恒平衡方程、应力平衡方程、质量守恒平衡方程、几何方程、物理方程、初始及边界条件，解出了单一冷源平面轴对称问题的解析解。

In this topic, the dynamic analysis methods for piezoelectric vibrator are studied systematically based on the theoretical model, FEM numerical experimentation and FEM governing equation for given compound-mode vibrator, and some valuable conclusions are obtained. The main work accomplished is summarized as follows: 1.Elaborate the main modeling methods for piezoelectric vibrator and the significance and necessity to study the dynamic characteristics of piezoelectric vibrator which emphasize the urgency of this paper. 2.Take the bending deformation induced by piezoelectric ceramic as example, the energy transfer mechanism of electric energy to mechanical energy are analyzed; the motion and force transfer mechanism are analyzed for the longitudinal-bending vibrator. 3.Based on mode assumption and Hamilton principle, the coupling model of piezoelectric vibrator of linear USM is built; moreover, the equivalent circuit model is obtained and a coupling equation represents the relation between electric parameters and mechanical parameters is derived which provides foundation to match the vibrator and driving circuit. 4.Combine the constitutive equation of piezoelectric ceramic with elastic-dynamical equation, geometric equation in force field and the Maxwell equation in electric field and the corresponding boundary condition equation, the FEM control equation for piezoelectric vibrator of USM to solve dynamic electro-mechanical coupling field is established by employing the principle of virtual displacement. The equation lays the foundation to study the non-linear constitutive equation of piezoelectric ceramic driven by high-power. 5.Define the dynamic indexes of characteristic of vibrator and carry out variable parameters simulation by calculating the model parameters and the electric characteristics of vibrator are simulated according to the equivalent circuit model. By numerical experimentation, the working mode of vibration of vibrator and the shock excitation results of the working frequency band which provides the mode frequency to realize bimodal are analyzed. Detailed calculation of the electro-mechanical coupling field parameters is made by programming the FEM control equation.

本课题从理论模型、有限元数值试验、有限元控制模型等方面以复合振动模式振子为例对超声电机压电振子的动力学特性及其分析方法进行了全面系统地研究，得出了许多有价值的结论，主要概括如下： 1、阐述了目前针对超声电机压电振子的主要建模方法，对压电振子动态特性的研究意义和必要性进行了论述，突出了本文研究内容的迫切性； 2、以压电陶瓷诱发弹性体发生弯曲变形为例，分析了压电陶瓷通过诱发应变来实现机电能量转换的机理；对基于纵弯模式的压电振子的运动及动力传递机理进行了分析； 3、基于模态假定，利用分析动力学的Hamilton原理，建立了面向直线超声电机压电振子的机电耦合动力学模型，并据此建立了压电振子的等效电路模型，导出了电参量与动力学特性参量的耦合方程，为压电振子与驱动电路的匹配提供了依据； 4、从压电陶瓷的本构方程出发，综合力场的弹性动力学方程、几何方程、电场的麦克斯韦方程以及相应的边界条件方程，采用虚位移原理，建立了压电振子动态问题机电耦合场求解的有限元控制方程，为研究其大功率驱动下的非线性本构模型奠定了基础； 5、界定压电振子的动力学特性指标，对压电振子的机电耦合动力学模型参数进行计算及变参数仿真；依据等效电路模型，对压电振子的电学特性进行了仿真分析；通过有限元数值实验，对压电振子工作模态附近的模态振型及工作频率附近的频段进行了激振效果分析，找出了实现模态简并的激振频率；利用有限元控制方程，通过编程计算，对压电振子的力电耦合场参数进行了详细计算，得出了一些有价值的结论。

We have no common name for a mime of Sophron or Xenarchus and a Socratic Conversation; and we should still be without one even if the imitation in the two instances were in trimeters or elegiacs or some other kind of verse--though it is the way with people to tack on 'poet' to the name of a metre, and talk of elegiac-poets and epic-poets, thinking that they call them poets not by reason of the imitative nature of their work, but indiscriminately by reason of the metre they write in.

索夫农 、森那库斯和苏格拉底式的对话采用的模仿没有一个公共的名称；三音步诗、挽歌体或其他类型的诗的模仿也没有——人们把&诗人&这一名词和格律名称结合到一起，称之为挽歌体诗人或者史诗诗人，他们被称为诗人，似乎只是因为遵守格律写作，而非他们作品的模仿本质。

The relationship between communicative competence and grammar teaching should be that of the ends and the means.

交际能力和语法的关系应该是目标与途径的关系。