展开

By analyzing several typical problems concerned with convection heat transfer and comparing the numerical results with the corresponding literatures, the second order full extension ETG finite element method is proved to be of better accuracy and stability.

通过几个典型的对流换热问题的算例分析，并与相关文献比较，证明了二阶全展开ETG有限元法在流场和温度场的计算中都具有较好的稳定性和较高的精度，适于求解对流换热问题。

LES cooperated with the second order full extension ETG finite element method is applied to simulate three typical problems concerned with convection heat transfer with sufficient experimental data. By comparing the numerical results with the experimental results, LES is proved to be of better accuracy and stability when it is used to solve the problems concerned with convection heat transfer. The time history of the flow field and temperature field can be reflected better, and abundant information of the fields can be obtained. Furthermore the details of the change in the vortex structure can be captured.

应用大涡模拟与二阶全展开ETG有限元离散格式相结合的方法对具有实验基础的三个典型对流换热问题进行了数值模拟，并将模拟结果与相应的实验结果进行对比，证明了大涡模拟应用于对流换热问题中具有较高的稳定性和精度，能够较好地反映流场和温度场的时变过程，提供丰富的温度场和流场信息，捕捉流场中旋涡结构的变化细节，尤其适合于边界形状复杂的区段内含有大尺度各向异性涡的流动和换热问题的计算。

While the second order full extension ETG finite element method is applied to solve the problems concerned with natural convection and forced convection, different discretization schemes are deduced respectively. Then the equations are solved by using the technology of variable bandwidth and mass diagonal matrix.

详细推导了应用二阶全展开ETG有限元法求解自然对流和强制对流问题时的有限元列式，并应用压力校正法与质量矩阵对角化及变带宽压缩存储技术对方程进行求解。

The mechanical parameters in the model are treated as random variables and it is then resolved with Taylor extension stochastic finite element method, The distribution characteristics of the pore pressure, the effective stress and the displacement are researched by treating the mechanical parameters of the rock as random variables. The sensitivities of the pore pressure, the effective stress and the displacement to the random mechanical parameters are also analyzed.

视模型中的参数为随机变量，采用Taylor展开随机有限元法对该模型进行数值模拟，研究参数具有随机性情况下耦合场中孔隙压力、有效应力，位移等场变量的随机分布特征及孔隙压力、位移等场变量对参数的灵敏度。

Thus LES is proved to be suitable to simulate the flow and temperature fields of large scale vortices with complex geometric boundaries. LES cooperated with the second order full extension ETG finite element method is applied to simulate the forced convection heat transfer around two square cylinders arranged side by side. While the boundary conditions are symmetrical, the time history and power spectrums of drag coefficient, lift coefficient, averaged Nusselt number at the wall, and the streamwise velocity and temperature on the symmetrical points are calculated. The results show that the power spectrums are all almost symmetrical.

应用大涡模拟与二阶全展开ETG有限元离散格式相结合的方法对间距比为1.5的条件下横掠并列双方柱强制对流换热问题进行了数值模拟，通过边界条件对称时，对并列双方柱对称点上的速度和温度以及方柱的阻力系数、升力系数和壁面平均Nu数进行的时域分析和频域分析，得到了在对称边界条件下并列双方柱对称点上的速度和温度以及方柱的阻力系数、升力系数和壁面平均Nu数的功率谱均基本对称的结论。

Like Fourier analysis, any function with finite energy can be expanded on the orthonormal wavelet bases.

与Fourier分析方法一样，任意的能量有限函数可以用小波正交基展开。

Using numerical simulation technology and method of orthogonal experiment design and single factor rotating optimization, this thesis makes a study of "lost core injection ", thus achieve the optimization of the parameters of molding process, to offer basic reference when developing production technology and mould of the plastics intake manifold. Based on the study of the status in quo and development trend of weight reduction on automobile, the application of plastics to automobile and intake manifold, then under the guidance of theory model and numerical simulation technology in the process of high polymer material, this thesis launches flowing main research work: First of all, on the basis of the three-dimensional model of the part and finite element net model, several designs of gating and running system are numerically simulated and analyzed via MPA of Moldflow.

本文在对当今汽车轻量化、零部件塑料化以及的汽车进气歧管塑料化的发展现状和发展趋势进行了研究和简要介绍，然后在高分子材料成型过程中的理论模型和数值计算方法的指导下，展开主要的研究工作：首先，在零件三维模型和有限元网格模型的基础上，使用Moldflow 的MPA模块对塑料进气歧管的多个浇注系统设计方案进行数值模拟，通过分析各个方案的充填质量、熔接线位置及数量等指标，得到了综合质量较高的4 个进料口的浇口位置及半限制型浇口大小的浇注系统。

Based on Collins integral formula and the expansion of the hard aperture function into a finite sum of complex Gaussian functions,the approximate analytical expression of the diffraction field of Gaussian beam by a circular disc is derived,and its characteristics are analyzed by the numerical calculation and numerical simulation.

基于圆孔光阑函数展开为复高斯函数和的方法，用Colins积分公式，导出了高斯光束照射下圆盘衍射的光场近似解析表达式，经计算机数值计算，对高斯光束照射下圆盘衍射的衍射特性进行了详细的分析

With aperture expanded as the sum of finite complex Gaussian terms, a more practical approximate analytical solution of fractional Fourier transform of Gaussian beam in an apertured paraboloid refracting system is obtained and also numerical investigation is presented.

通过将孔径函数展开为有限项复高斯函数之和，得到了高斯光束在受孔径约束的抛物面折射系统中分数傅里叶变换较符合实际的近似解析表达式，并进行了数值模拟。

Based on the Collins formula, the analytical propagation equations for a Gaussian beam through a multiple spatial filter system are derived by using the methods of the matrix decomposition and expanding the aperture function into a finite sum of complex Gaussian function .

以Collins衍射积分公式为基础，利用A0CD矩阵分解与物理实现的技巧，以及将硬边光阑窗口函数展开为有限个复高斯函数之和的方法，推导出了高斯光束通过多级空间滤波器系统的传输方程，并用数值计算加以说明。

Neither the killing of Mr Zarqawi nor any breakthrough on the political front will stop the insurgency and the fratricidal murders in their tracks.

在对危险的南部地区访问时，他斥责什叶派民兵领导人对中央集权的挑衅行为。

In fact,I've got him on the satellite mobile right now.

实际上 我们已接通卫星可视电话了