数值方程

Firstly the k-e two-equation turbulence model is used in numerical simulation of the flow field ,compared with the practical measures and tests, good accordance achives. This method can bring great convenience in analyzing aerodynamical field of boiler. Secondly the method of ash-composition, ash-melting-point, XRD is used in analyzing the phase transformation in the course of dynamic slagging test, so we can describe the process of slagging comparatively accurately. Last this paper introduces a kind of fuzzy mathematics model which comprises an assemblage combined by seven change factor.

接着采用标准k—ε双方程模型对炉内冷态空气动力场进行了数值模拟，并与实际锅炉燃烧器冷态调试试验结果对比，结果吻合较好，这为我们分析炉内流场提供了参考；其次对锅炉静态、动态特性试验，采用灰成分分析、灰熔点测试及X光衍射物相分析方法，较为准确的描述了实际锅炉结渣过程；为了准确的判断出水煤浆的结渣倾向，本文对锅炉结渣的七个影响因素提出了模糊综合判断模型，正确的反映出了该水煤浆的结渣倾向。

These have been developed by the numerical integration of the differential equations of gas motion for a spherical blast wave in air.

这些都是根据空中球形爆震波气体运动的微分方程的数值积分得到的。

Governing equation discrete, solving of the conjugated algebraic equation set and SIMPLE method are also discussed in this paper.

同时对方程离散、方程组的耦联求解及SIMPLE算法等数值计算以及湍流及其模型等问题进行了论述。

Based on a modified algebraic Riccati equation, this paper provides the conditions for the existence of the previous performance robust controllers.

基于一个修正的代数Riccati方程，给出了上述性能鲁棒控制器的存在条件及解析表达式，并举出相应的数值例子，以说明本文设计方法的简单性与直接性。

Furthermore,3-D FEM algorithm based on the division of tetrahedral grids is deduced by the equations of point electrical source field.

同时，从点电源场满足的方程出发，本文推导了三维复杂地形条件下有限元数值模拟算法，并编制了计算程序。

A high-order alternating direction implicit method for solving two or three dimensional heat equations is proposed. The method is fourth order in space and second order in time.

提出了数值求解二维和三维热传导方程的高精度交替方向隐式方法，其空间为四阶精度，时间为二阶精度，并通过Neumann方法证明是无条件稳定的。

Based on the second- and fourth-order compact difference formulas for second-order derivatives and the idea of weighted average, two classes of the alternating direction implicit method are proposed for solving two-dimensional wave equation. The methods are of accuracy O (T^2+h^4) and O (T^4+h^4) respectively. Stability conditions are obtained by Fourier analysis method.

基于二阶微商的四阶紧致差商逼近公式及加权平均思想，提出了数值求解二维波动方程的2种精度分别为O(т^2+h^4)和O(т^4+h^4)的交替方向隐式格式，以及与其相匹配的第一个时间层的同阶离散格式，并且通过Foulier方法分析了格式的稳定性。

The alternating group iterative method is used to solve the implicit scheme and the Crank-Nicolson scheme of the dispersive equation.

数值试验对色散方程的隐格式与Crank-Nicolson格式分别应用交替分组迭代求解。

The mutual coherence and angular correlation function of scattered wave from two dimensional rough surfaces is derived with Integral Equation Model and then calculated for perfectly conducting rough surfaces, then the scattering of incident pulse wave with different shape is calculated and the shape of scattered pulse is presented.

采用积分方程法推导出了二维粗糙面的双频互相关和角相关函数，数值计算了具有不同粗糙度的良导体粗糙面的双频互相关函数，在此基础上分别计算了二维粗糙面对δ脉冲、Gaussian脉冲和矩形脉冲的散射，并给出了散射脉冲的波形。

By direct numerical simulation of Navier-Stokes equations we investigate the three-dimensional evolution of a mixing layer, the three-dimensional merger of two parallel vortex tubes and reconnection of two antiparallel vortex tubes in the thesis.

本文用拟谱方法求解Navier-Stokes方程，对小扰动下平面混合层随时间的演化、同向平行涡管的三维合并和反向平行涡管的重联进行了直接数值模拟。

For a big chunk of credit-card losses; the number of filings (and thus charge-off rates) would be rising again, whether

年美国个人破产法的一个改动使得破产登记急速下降，而后引起了信用卡大规模的亏损。

Eph. 4:23 And that you be renewed in the spirit of your mind

弗四23 而在你们心思的灵里得以更新