数值计算

Then the boundary element integral equation of interior and exterior form is deduced in detail, also the form with corner coefficient. The significance for numerical calculation and principle of the singular integral is analyzed, and a non-isoparametric transformation method is presented to calculate weak singular integral and Cauchy integral, the method presented provides us a very simple way to computer the two kinds of singular integral of Helmholtz boundary integral equation, and it is easy to program in computer. After the difficulty of the calculation for multi-frequency of Helmholtz boundary element is explained, a method named SECHIEF (Series Expansion Combined Helmholtz Integral Equation Formulation), which is focused on the computational efficiency, is presented.

对结构声辐射的边界积分方程的内部形式与外部形式进行了详细的推导，给出了角点系数的计算方法与边界积分方程的形式，在此基础上，分析了奇异积分产生的原理及其对数值计算的重要性，提出了一种计算奇异积分的非等参(来源：Ae8a8BC论文网www.abclunwen.com)单元的变换方法，该方法给Helmholtz 声学边界积分方程中的弱奇异积分与Cauchy 奇异积分的计算以及编程提供了极大便利。

After compared with other several numerical analysis methods, Fourier series fitting method is applied to calculate the parameters of motion of the mechanism.

最后通过对几种数值计算方法在计算机上进行实际计算比较，确定采用基于最小二乘原则的Fourier级数拟合方法计算出机构的运动参数。

The material job and main conclusion are as follows:(1) A simple boundary orthogonalization procedure independence grids generation method is put forward on the base of algebraic grid generation method; Data structure and computational model on interface are established aiming at blocks of structured grids.

本文针对粘流场数值模拟技术的研究现状和发展动态作了比较全面的回顾与展望，重点研究了网格生成技术、数值求解技术、湍流模型技术和动边界模拟技术，在此基础上建立了模拟自由面湍流场的数学模型，并成功地应用到二维溢流坝和带闸墩的三维溢流坝过坝水流的数值计算。

On the basic of above job a mathematical model of simulation turbulent flow with free surface is established and triumphantly applied to numerical computation on 2D spillway and 3D spillway with frusta of brake.The material job and main conclusion are as follows:(1)A simple boundary orthogonalization procedure independence grids generation method is put forward on the base of algebraic grid generation method; Data structure and computational model on interface are established aiming at blocks of structured grids.

本文针对粘流场数值模拟技术的研究现状和发展动态作了比较全面的回顾与展望，重点研究了网格生成技术、数值求解技术、湍流模型技术和动边界模拟技术，在此基础上建立了模拟自由面湍流场的数学模型，并成功地应用到二维溢流坝和带闸墩的三维溢流坝过坝水流的数值计算。

Numerical calculations were accomplished by the directly numerical method of the singular integral equations and a large amount of statistical results were obtained. So the issue of influence was systematically solved.

最后利用奇异积分方程的数值解法进行了数值计算，得到了大量的数值结果，从而系统地解决了一般倾斜裂纹对界面的影响分析。

A 550kV SF6 circuit breaker has been taken as an example, the gas blast flow in no-load breaking process has been simulated, the results show that the basic solution of Euler equation set derived is correct, which lays the foundation for developing the Boundary Element Method of numerical solution for the time-dependent compressible flow of fluid.

作为数值模拟实例，文中对550kV SF6断路器空载开断过程中吹弧气体流动规律进行了数值模拟，其结果证明文中导出的基本解是正确的，从而为进一步开发求解非定常可压缩气体流动的边界元数值计算法奠定了基础。

By the numerical analysis of the ultimate bearing capacity of two- and three-dimensional footing under combined loading mode, the results show that the effect of alteration of underground water lever on bearing capacity of three-dimensional foundation is more than on that of two-dimensional foundation, the effect of soil gravity on bearing capacity of three-dimensional foundation is more than that of two-dimensional foundation. At the same time, the numerical calculation process of ABAQUS indicates that whether the geostatic stress is balanced or not has great effect on the numerical convergence. In view of the effect extent of dilation angle of soil on the ultimate bearing capacity and the failure pattern of foundation, the condition of two-dimensional plane strain is higher than that of the three-dimensional foundation.

复合加载模式下，通过对三维矩形基础和二维条形基础进行数值分析，结果表明：黏性土地基中地下水位的变化，对三维矩形基础极限承载力的影响程度高于对二维条形基础的影响；在求解地基极限承载力的过程中，土体重度对三维矩形基础的影响明显高于对二维条形基础的影响，同时ABAQUS数值计算过程表明，地基土体地应力能否合理平衡，对数值求解过程中是否收敛有很大的影响；就土体剪胀角对地基极限承载力的影响程度而言，二维平面应变情况下土体剪胀角对极限承载力的影响比三维情况下的影响更明显，即土体剪胀角对条形基础极限承载力的影响高于三维矩形基础。

There are profound study on the internal heat and mass transfer of cooling tower in unwindy weather at present.

在目前冷却塔数值研究的基础上，本文以逆流湿式自然通风冷却塔为研究对象，建立冷却塔内外空气流动和传热传质的数学和物理模型，并运用数值计算方法对冷却塔进风口附近的流场进行了数值模拟。

Based on them, distribution laws of subgrade temperature field under fluctuant boundary temperature cycle conditions are analyzed, and different ratios of slope for general subgrade and different status when there are or not banquettes are compared by laboratory simulation and numerical analysis; thermal insulation and cooling effect of thermal insulation slab, broken stone and non-power heat pipes is respectively investigated under the trend of elevated temperature by numerical analysis, laws of subgrade deformation are predicted under the trend of elevated temperature and influences of subgrade thaw settlement on pavement stress are studies by numerical computation for observation data of representative road sections selected.

为研究青藏公路冻土病害处治对策，从青藏公路2002年～2004年冻土病害整治工程实际出发，在系统分析研究青藏公路病害及发生机理的基础上，运用室内模拟试验、数值分析方法，依托处治冻土病害路段实际使用的隔热板路基、碎石路基、无动力热棒路基等进行现场试验，分析边界温度周期波动条件下的路基温度场分布规律，同时进行一般路基不同边坡坡率的对比研究及有无护坡道的对比研究；运用数值分析方法，对气温升高趋势下隔热板、碎石、无动力热棒的隔热降温效果进行了研究；选择代表性路段观测资料，运用数值计算的方法，进行升温趋势下的路基变形预测，研究路基融沉变形对路面应力的影响。

A comprehensive review and expectation about researching status in quo and development trends of viscous flow numerical simulation technique are given in this paper and grids generation methods, numerical computation methods, turbulent model and moving boundary simulation methods are the emphasis study in the paper. On the basic of above job a mathematical model of simulation turbulent flow with free surface is established and triumphantly applied to numerical computation on 2D spillway and 3D spillway with frusta of brake.

本文针对粘流场数值模拟技术的研究现状和发展动态作了比较全面的回顾与展望，重点研究了网格生成技术、数值求解技术、湍流模型技术和动边界模拟技术，在此基础上建立了模拟自由面湍流场的数学模型，并成功地应用到二维溢流坝和带闸墩的三维溢流坝过坝水流的数值计算。

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应，而且减少跟风的可能性。