隐式差分格式

In the light of the complex, high-level and non-linear feature of the mathematical model which describe the transport of the coalbed methane, this paper study the fully-implicit solving method of the mathematical model in detail. Based on the complexity of the algebraic equations which are formed eventually, according to the alternating direction implicit difference pattern, this paper use the iterative method and the fully main element Gauss-Jordan eliminating method to solve equations, which is to use the iterative method to determine coefficient matrix and use the fully main element Gauss-Jordan method to solve th linear algebraic equation group, at the same time of studying the solving method of the mathematical model, according to the devising requirement of FORTRAN77 program structure, this paper draw up computer program and form the corresponding computer model, and verify the validity and reliability of the model in theory by operating the model.

重点研究了模型内、外边界及有关参数的处理，针对描述煤层甲烷运移的数学模型是一个复杂、高阶非线性数学模型的特点，详细研究了模型的全隐式求解方法，根据最后形成的代数方程组的复杂性，按交替方向隐式差分格式，采用迭代与全选主元高斯约当消去法相结合的方法求解方程：即确定系数矩阵采用迭代法，求解线性方程组时采用全选主元高斯约当消去法，在研究模型解法的同时按FORTRAN结构化程序设计的要求，编制计算机程序，形成相应的CBMRS计算机模型，并通过模型的运行从理论上证明了模型的正确性与可靠性。

VOF equation use Lax-Wendroffgeshi scheme with precision of two steps. Pressure of host field is turned into initial-boundary value problem of variable coefficient parabolic equation on regular border. We utilize implicit difference method to solve it.

VOF方程的离散求解使用Lax-Wendroffgeshi格式，这种格式具有二阶精度；主场压力的求解转化为固定边界上变系数抛物型方程的初边值问题，采用隐式差分格式。

In order to get the numerical solution, the paper devises a three hierarchic implicit scheme which eliminates the strict restriction of explicit scheme, thus, it can be used in more areas. By using the energy estimation method, the convergence and stability of the difference scheme are proved and the scheme is second order convergence for time and space.

对求解方程构造了一个三层隐式差分格式，消除了显格式的稳定性对计算步长的严格限制，使之适用范围更广，并用能量估计的方法严格证明了差分格式的收敛性与稳定性，该格式对于时间和空间均具有二阶收敛性。

These methods will be studied separately with the Euler implicit difference scheme and the Euler explicit difference scheme.

第一种方法是两层有限元Galerkin方法，第二种方法是修正有限元Galerkin方法，对这几种算法我们分别在欧拉显式差分格式和欧拉隐式差分格式下进行讨论研究。

This model used the finite—difference approximation to the advection— dispersion equation. The spatial derivatives in the flow equation are approximated by central difference written about grid—block boundaries and time derivatives are approximated by a fully implicit backward scheme.

水流方程的空间导数采用中心差分格式离散，时间导数采用隐式差分格式离散，建立了土壤水分和污染物在各种饱和度的条件下迁移转化方程耦合求解的二维数值计算模型。

It adopts the variable step length scheme to evaluate at the connection point, and adopts the implicit difference scheme to evaluate in the same rod.

3运用在均质处采用隐式差分格式、节点处采用变步长的有限差分的混合方法求解抽油杆柱的波动方程。

This method adopts the variable step length scheme to evaluate at the connection point, and adopts the implicit difference scheme to evaluate in the same rod.

在进行数值求解时，在抽油杆柱均质杆段处采用隐式差分格式，而抽油杆柱在组合杆柱相邻联结点处则采用变步长的有限差分格式。

By introducing the parameter , construct a new kind of weighted implicit difference scheme for (1+1)-dimension nonlinear Sine-Gordon equation and the generalized nonlinear Sine-Gordon equation respectively. Give out an ADI scheme for (2+1)-dimension nonlinear Sine-Gordon equation.

通过引进参数，分别为（1+1）维的非线性Sine-Gordon方程和广义的非线性Sine-Gordon方程建立了它们的加权隐式差分格式，给出了（2+1）维的非线性Sine-Gordon方程的ADI格式。

According to the computational stability analysis conducted to the linear term time difference scheme in simple harmonic motion equation, one new semi-implicit integration scheme also is designed. By adopting a kind of revised time-explicitdifference scheme to these linear terms still included in spectral model governing equations, this defect of spectral model only partly used in semi-implicit integrating scheme, can be overcome to some degree.

以简谐振动方程中线性项时间差分格式对其计算稳定性影响为理论依据，本文设计了一种新谱模式半隐式时间积分方案，此方案通过对一般谱模式求解框架中那些隐含的线性项采用了一种显式修正的差分格式，可有效克服其国际谱模式半隐式时间求积方案实质上只是部分应用了半隐式差分格式的问题。

The initial-boundary value problem of dispersive equation is a kind of mathematical model, in this paper, it has been followed the ways of other scholars and used a new method and got a new difference scheme. It was a three layers ten-point implicit difference schemes.

色散方程的初边值问题是在孤立波这样的物理现象中抽象出来的一类数学模型，在前人构造的众多差分格式的基础上，使用新的构造方法，给出了该问题的三层十，点隐式差分格式。

With Death guitarist Schuldiner adopting vocal duties, the band made a major impact on the scene.

随着死亡的吉他手Schuldiner接受主唱的职务，乐队在现实中树立了重要的影响。

But he could still end up breakfasting on Swiss-government issue muesli because all six are accused of nicking around 45 million pounds they should have paid to FIFA.

不过他最后仍有可能沦为瑞士政府&议事餐桌&上的一道早餐，因为这所有六个人都被指控把本应支付给国际足联的大约4500万英镑骗了个精光。