查询词典 finite difference approximation

In the simplified model, the governing equation of heat conduction is discretized using implicit finite difference method, and the computational domain is discretized using cell centered scheme, and the solution of Maxwell equation is used to determine the distribution of the internal heating sources.

使用的简化模型中热传导方程的离散采用隐式差分法、区域的离散采用内节点法，并以Maxwell方程的解确定内热源分布。

From finite difference equation of unsteady-state heat conduction ,according to vonNeumann method about scheme stability,the explicit scheme stability condition of two dimension computational heat conduction was given.

从非稳态导热的离散方程出发，根据VonNeumann的格式稳定性判别方法，给出二维导热数值计算显式格式的稳定性条件。

The three-dimensional motion equation of the cable-damper system is established and discretized by the finite difference method.

建立斜拉索—阻尼器系统的三维运动方程，并采用有限差分法进行离散化。

The truncation error of CSCD is derived and compared with some symmetric finite difference methods having the same order of accuracy,which shows that CSCD has the smallest coefficients in error terms.

从定性角度，得出同阶中心差分格式中，CSCD格式的截断误差系数最小的结论。

With the investigation of the domestic and foreign literature systematically, the bases on the domestic and foreign present research and the comprehensive utilizations of the various knowledge of fluid mechanics in porous medium, reservoir engineering, mathematical physics, perforation completion, numerical simulation and so on, this article takes numerical simulation of gas reservoir of water solubility as the research aim which has completed following research works and obtained the corresponding research results: it analyzes the nature of the Water-soluble gas and formation water as well as the influent factors of the solubility through the study of massive materials; It establishes mathematical models three-dimension, the dual medium, the gas-water phase through the way of finite difference in the migration of water-soluble gas, which describes the entire process of release, migration and production in formation, where it considered the problems of variable bubble point; According to the numerical models of gas reservoir of water solubility it provides solution procedure that based on black oil model; It discovers that there will obtain the good effects in the lowly speed of development through simulation; the reinjection of formation water may largely enhance the produce degree of water-soluble gas when we consider reinjection in simulator; It considered the influence of perforated completion on development so as to increase the simulator"s versatility, It discovers that the simulator may reflect the conditions of development when we exanimate he simulator"s reliability with the empirical datum.

本文以水溶性气藏数值模拟研究为研究目标，在系统调研国内外文献、深入分析国内外研究现状的基础上，综合利用渗流力学、油气藏工程、数学物理方法、射孔完井以及数值模拟理论等多方面的知识，完成了以下研究工作并取得相应的研究成果；①通过对大量的资料调研，分析了水溶气、地层水性质、储层地质性质以及影响气体在水中溶解度的因素。②考虑到由于高压产生的大量水力裂缝，采用有限差分方法建立水溶气运移的三维、双重介质、气-水两相全隐式数学模型，该模型描述了水溶气在地层中的释放、运移和采出的整个过程。③在原有黑油模型的基础上，根据水溶性气藏数值模型编制了该数值模型的求解程序，该程序可以求解单重、双重介质两种情况。④通过模拟不同开采速度对水溶气开发效果的影响，发现开采速度较慢的时候可以取得较好的开采效果。⑤在模拟器中考虑了注水对水溶性气藏开发的影响，地层水回注可以大幅度提高水溶气的采出程度。⑥为增加模拟器的通用性，在模拟器中考虑了射孔完井方式对开采的影响。⑦检验模拟器计算的可靠性，发现在使用实验数据对水溶性气藏进行模拟时，模拟器可以很好的反映气藏开发的状态。

The finite field method is used to calculate difference of dipole moment of theground state and excited state.

然后利用上述结果，用少态模型计算分子的双光子吸收截面。

Taylor series expansion theorem is a very important method for the construction of finite difference.

时域有限差分法是计算电磁领域中的一类非常重要的研究工具。

Second-order-accuracy non-oscillatory and non-free-parameters dissipative finite difference scheme and explicit time-marching method were used to obtain numerical solutions.

采用二阶精度无波动、无自由参数的耗散差分格式和显式时间推进法求出数值解。

The time-marching method and explicit finite volume difference scheme are employed to solve the flow inside the turbo-machinery.

教授的粘性体积力法来模拟粘性对叶轮机械内部流动的影响，采用时间推进法和有限体积差分格式对叶轮机械内部的流动进行求解。

An explicit finite difference scheme is constructed to simulate Baldwin-Barth one-equation turbulence model. By using Von Neumann analysis method, its stability condition is obtained.

在非结构网格上构造格心显式格式求解Baldwin-Barth-方程湍流模型，并运用Von Neumann稳定性分析方法，给出〓格式稳定性条件。

We have something to do in the new stage.

在这段崭新的时期中，我们有一些要做的。

The difference between tourism decision-making under uncertainty and risky tourism decision-making is indistinctive.

其中不确定性旅游决策和风险旅游决策的界线比较模糊，两者的区分是相对的。