查询词典 finit element method

In the last part, analysis of the sound field around the shell of the fan is done with combining finite element method and boundary element method by using software ANSYS and SYSNOISE.

第四部分分析风机外壳周围声场，结合有限元法和边界元法，应用ANSYS和SYSNOISE软件，建立声场边界元模型。

In this dissertation the"Penalty"finite element method was employed to compute the velocity of the three-dimensional flow of power-law fluid in a profile die. In order to decrease the needed computer memory and raise the stability of numerical simulation, a set of decoupled methods such as PFEM, pseudo-body force method and transformation of momentum equation to the elliptic equation was developed to establish the general finite element equations to compute the distributions of velocity and viscoelastic stress of the three-dimensional viscoelastic flow of the Phan ThienTanner fluid in a profile die. During numerical simulation of the extrudate swell of the PTT fluid, the flow in the die and out of the die was analyzed separately, which demands less computer memory.

本文建立了求解挤出口模内幂律流体流动速度场的通用三维罚有限元模型；对于非线性粘弹性的Phan Thien-Tanner流体，为了降低模拟计算对计算机硬件的要求，并使模拟计算更加稳定，采用了一种去耦算法，包括罚有限元方法、拟体力方法和动量方程的椭圆类方程转化方法，并建立了求解速度场和粘弹性应力场的总体有限元方程；对于PTT流体的挤出胀大问题，提出了挤出胀大熔体口模内外分离模拟法，这样可以显著降低数值模拟对计算机硬件的要求。

In this dissertation the"Penalty"finite element method was employed to compute the velocity of the three-dimensional flow of power-law fluid in a profile die. In order to decrease the needed computer memory and raise the stability of numerical simulation, a set of decoupled methods such as PFEM, pseudo-body force method and transformation of momentum equation to the elliptic equation was developed to establish the general finite element equations to compute the distributions of velocity and viscoelastic stress of the three-dimensional viscoelastic flow of the Phan ThienTanner fluid in a profile die. During numerical simulation of the extrudate swell of the PTT fluid, the flow in the die and out of the die was analyzed separately, which demands less computer memory. The key techniques used in numerical simulation of the three-dimensional extrusion from dies such as decision of boundary conditions, creation of initial velocity field, selection of penalty factor, high Weissenberg number problem , regeneration of the free surface were studied in detail.

中文题名聚合物异型材口模挤出三维流动研究副题名外文题名 Study on three-dimensional flow of polymer melts during the process of profile extrusion from dies 论文作者涂志刚导师柳和生包忠诩教授学科专业材料加工工程研究领域\研究方向学位级别博士学位授予单位南昌大学学位授予日期2001 论文页码总数148页关键词挤出成型聚合物材料挤出口模聚合物异型材馆藏号BSLW /2003 /TQ320 /9 本文建立了求解挤出口模内幂律流体流动速度场的通用三维罚有限元模型；对于非线性粘弹性的Phan Thien-Tanner流体，为了降低模拟计算对计算机硬件的要求，并使模拟计算更加稳定，采用了一种去耦算法，包括罚有限元方法、拟体力方法和动量方程的椭圆类方程转化方法，并建立了求解速度场和粘弹性应力场的总体有限元方程；对于PTT流体的挤出胀大问题，提出了挤出胀大熔体口模内外分离模拟法，这样可以显著降低数值模拟对计算机硬件的要求。

Based on Galerkin finite element method, a new upwinding finite element numerical model suitable for modeling wind driven current in shallow lakes is derived by introducing streamline upwinding method and the selective lumping coefficient matrix scheme.

从控制方程组出发，以 Galerkin有限元法为基础，引入沿流线加权的权函数(沿流线加权的迎风有限元法)和选择性集中系数矩阵方法，推导、建立了一适合于浅水湖泊风生流计算的二维迎风有限元数值模型。

The new calculation method of structural surfaces with different scales is given on the basis of block discrete element method in which contacts face to face. Moreover, a new discrete element model for simulating rock and soil blasting problem is built. The elements of new model can be split by itself in the program. There are small scale blocks around the charge, and large scale blocks are adopted in far zone.

在块体离散元面－面接触的基础上，给出不同尺度结构面的计算方法，建立离散元对岩土爆破模拟的计算模型，实现块体白分裂计算程序，在药包附近采用小尺度块体，远区采用大尺度块体，可以更为准确地描述爆破载荷下岩体结构面的尺寸效应。

This paper puts forward CS roof plate finite element model and its analyse method. The analysis result indicates that the finite element model and analyse method is appropriate and makes some analyse of the CS plates with different distributed steel.

本文提出了三步节能CS屋面板有限元模型建立以及分析方法，分析结果表明本文建立的有限元模型和采用的分析方法是合理的，并利用有限元方法对其他配筋形式的三步节能CS屋面板进行了分析。

In the cylindrical coordinates, the related basic formula and solve method of the equivalent boundary element method were established and derived, and a new contact element was introduced to model the hybrid of structure and soil.

同时建立并推导了在柱体坐标系下插入式大圆柱壳墩式结构的等效边界元数值分析的相关基本方程和求解方法，并提出了一种新的接触面单元以模拟结构和土体间不同材料的耦合关系。

Lastly we made a comparison between variational method and finite element method on the lateral loaded behaviour of barrette pile group, and also proved variational method is a feasible and efficiency method.

论文在最后一章采用有限单元法和变分法对壁板桩水平承载特性进行了对比验证，证实了应用变分法分析壁板桩承载特性是一种可行和有效的研究方法。

According to the studied results at present, the studied objects are mainly thin plate and beam about sound radiation mode, a method computed sound radiation mode of complex structure is presented in this dissertation, according to the results of the previous two chapter, a theoretical method to solve acoustical radiation mode and acoustical radiation efficiency of complex structure by boundary element method and acoustical radiation theory is posed, the acoustical radiation power is expressed as a Hermitian quadratic form, while the radiation modes is determined by general eigenvalue decomposing, and then the radiation efficiency is computed via the orthodoxy of radiation modes with regard to impedance matrix and average velocity matrix; lastly, the validity of the method is proved by pulsating sphere and radiating cube with analytical results. According to results of the form three chapter, the structure sound radiation sensitivity is studied in detail, the sound radiation power of structure can be expressed as positive Hermitian quadratic form, the sound radiation sensitivity can be expressed as two parts by partial differential with respect to design variable, which are sensitivity of boundary velocity and impedance matrix, combined with the theory of FEM and BEM, the structure sound radiation can be translated to the analysis of structure dynamic sensitivity and impedance matrix sensitivity. The theory posted in this dissertation is tested by the FEM software ANSYS and the software AAS programmed by author.

在前几章的基础上，通过结构声辐射的模态理论对结构的声辐射的机理进行了深入地探讨，针对目前声辐射模态的研究对象主要是简单的板和梁类结构，提出了一种计算复杂结构声辐射模态的方法，利用前两章研究所得的结论，将边界元方法与广义特征值的理论结合起来研究了复杂结构的声辐射模态与声辐射效率，先将结构的声辐射功率表示为一个正定的厄米特二(来源：ABb7C论文0909网www.abclunwen.com)次型，运用广义特征值分解求解了复杂结构的声辐射模态，然后利用声辐射模态关于阻抗矩阵与均方速度耦合矩阵的正交性，求解了复杂结构的声辐射效率，最后用具有解析解的脉动球与辐射立方体验证了该方法的有效性。

The method has the advantages of Rigid Body Limit Equilibrium Method and Finite Element Method. In this method, the whole equilibrium conditions are kept, and the deformation of material is considered to some extent.

利用一种改进的刚体极限平衡法——块体单元法进行边坡稳定分析，该方法兼有刚体极限平衡法和有限元法的优点，既满足全部的平衡条件，又在一定程度上考虑了材料的变形。

Effective local search tactics reaches local searchers when they are ready to buy - with every way that it is possible for them to buy from you.

有效的地方搜索策略达到当地的搜索，当他们准备购买-以各种方式，这是他们有可能从您那里进行购买。

The first two are periodic sentences for their beginnings; and the fifth and the last are also periodic sentences each for the embedding of a parenthetic structure.

1960年代中后期，当战后女权主义和当时的许多其他抗议运动在西欧和北美发展成某种势力时，性别的概念演绎成补充和延伸生物性别差异的概念。