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1.
二维抛物型偏微分方程的绝对稳定显格式   总被引:1,自引:0,他引:1  
提出了一个解二维抛物型偏微分方程初边值问题的绝对稳定分支三层显式差分格式,格式的局部截断误差阶为O(△t2+△x2+△y2).实算表明,格式的稳定性能与理论分析是一致的.  相似文献   

2.
利用待定参数法,对一维抛物型方程构造出了一个截断误差为O(△x^4+△x^4)的隐式差分格式,格式的稳定性条件为r=a△t/△x^2≤1/√2,可用追赶法求解。  相似文献   

3.
提出了一个解二维抛的型方程初边值问题的简单实用的显格式,证明了其截断误差阶是O,稳定性条件是α+β≠1/2且max{α,β}≤1/4,其中,α=α.Δt/Δx^2.β=α.Δt/Δy^2。  相似文献   

4.
曾文平 《应用数学》2004,17(2):250-256
对高阶Schrodinger方程эu/эt=i(-1)^mэ^2mu/эx^2m构造一族含双参数的三层高精度隐式差分格式.当参数α=1/2,β=0时得到一个两层格式.并证明了:对任意非负参数α≥0,β≥0该格式都是绝对稳定的,并且其截断误差阶达到O((△t)^2 (△x)^6).数值例子表明:本文所建立的差分格式是有效的,理论分析与实际计算相吻合.  相似文献   

5.
曾文平 《应用数学》2002,15(4):52-56
对一类演化方程δu/δt=aδ^2m 1u/δx^2m 1(a为常数,m为正整数)构造一族含双参数的三层高精度隐式差分格式。当参数α=1/2,β=0时得到一个双层格式。并证明了:该格式对任意非负参数α≥0,β≥0都是绝对稳定的,并且其截断误差阶为0((Δt)^2 (Δx)^4).数值例子表明:本文所建立的差分格式是有效的,理论分析与实际计算相吻合。  相似文献   

6.
本文考虑了具有齐次边界条件的对称正则长波方程的有限差分格式,提出了一个三层守恒的有限差分格式,证明了格式的收敛性和稳定性,从理论上得到了收敛阶为O(h2+τ2).通过数值试验表明,所提的方法是可靠有效的.  相似文献   

7.
对一维Neumann边界条件的线性双曲方程,利用有限差分方法建立高阶差分格式.由方程和边界条件得到在空间边界点的三阶和五阶导数值,进而分别在内点和边界点建立三点和两点紧差分格式,其截断误差关于时间和空间分别为二阶和四阶;利用离散的能量估计方法,分析差分格式的收敛性和稳定性;通过数值算例,验证理论分析结果.  相似文献   

8.
对高阶Schr dinger方程 u t=i( - 1 ) m 2mu x2m 构造一族含双参数的三层高精度隐式差分格式 .当参数α=1 /2 ,β =0时得到一个两层格式 .并证明了 :对任意非负参数α≥ 0 ,β≥ 0该格式都是绝对稳定的 ,并且其截断误差阶达到O( (Δt) 2 (Δx) 6) .数值例子表明 :本文所建立的差分格式是有效的 ,理论分析与实际计算相吻合  相似文献   

9.
文章考虑了具有齐次边界条件的广义对称正则长波方程的有限差分格式.提出了一个守恒并且线性非耦合的三层有限差分格式,由于格式在计算中只需要解三对角线性方程组,从而避免了其中的迭代计算.文中先讨论了一个离散守恒量,然后我们利用离散泛函分析方法证明了格式的收敛性和稳定性,从理论上得到了收敛阶为O(h~2+τ~2).通过数值试验表明,所提的方法是可靠有效的.  相似文献   

10.
高俊斌 《应用数学》1996,9(1):26-32
本文讨论样条空间S^13上的插值问题,导出了一类插值条件下样条插值的存在性与唯一性结论以及计算插值样条的递推格式,其主要结论是对四阶光滑的函数,插值样条可达2阶逼近度。  相似文献   

11.
对二维Neumann边界条件的线性双曲型方程建立了紧交替方向的隐格式.利用方程和边界条件得到在空间上的三阶与五阶导数的边界值,进而在内点、边界内点和边界角点分别建立9点、6点和4点紧差分格式;通过引进新的范数和L2范数估计L范数;借助能量估计、Gronwall不等式和Schwarz不等式等技巧,详细分析了差分格式在无穷范数下关于时间和空间分别为二阶和四阶收敛性,并给出了稳定性结果;通过数值算例,验证了理论分析结果.  相似文献   

12.
In this paper, we propose a difference scheme with global convergence order $O(\tau^{2}+h^4)$ for a class of the Caputo fractional equation. The difficulty caused by the spatially variable coefficients is successfully handled. The unique solvability, stability and convergence of the finite difference scheme are proved by use of the Fourier method. The obtained theoretical results are supported by numerical experiments.  相似文献   

13.
In order to obtain the numerical solution for a one-dimensional parabolic system, an unconditionally stable difference method is investigated in [1]. If the number of unknown functions is M, for each time step only M times of calculation are needed. The rate of convergence is $O(\tau+h^2)$. On the basis of [1], an alternating calculation difference scheme is presented in [2]; the rate of the convergence is $O(\tau^2+h^2)$. The difference schemes in [1] and [2] are economic ones. For the $\alpha$-$th$ equation, only $U_{\alpha}$ is an unknown function; the others $U_{\beta}$ are given evaluated either in the last step or in the present step. So the practical calculation is quite convenient. The purpose of this paper is to derive a trilayer difference scheme for one-dimensional parabolic systems. It is known that the scheme is also unconditionally stable and the rate of convergence is $O(\tau^2+h^2)$.  相似文献   

14.
In this article, we study a sequence of finite difference approximate solutions to a parabolic system, which models two dissimilar rods that each rod is fixed at one end and is free to expand or contact at the other end. A finite difference scheme is derived by the method of reduction of order on nonuniform mesh. The unique solvability, unconditional stability, and convergence of the difference scheme are proved. The convergence order is of order two in both time and space. The convergence of iterative algorithm for the difference scheme are also discussed. A numerical example is presented to demonstrate the theoretical results. © 2006 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2007  相似文献   

15.
In this paper, a boundary feedback system of a class of non-uniform undamped Timoshenko beam with both ends free is considered. A linearized three-level difference scheme for the Timoshenko beam equations is derived by the method of reduction of order on uniform meshes. The unique solvability, unconditional stability and convergence of the difference scheme are proved by the discrete energy method. The convergence order in maximum norm is of order two in both space and time. The validity of this theoretical analysis is verified experimentally.  相似文献   

16.
In this paper, a compact finite difference scheme with global convergence order $O(\tau^{2}+h^4)$ is derived for fourth-order fractional sub-diffusion equations subject to Neumann boundary conditions. The difficulty caused by the fourth-order derivative and Neumann boundary conditions is carefully handled. The stability and convergence of the proposed scheme are studied by the energy method. Theoretical results are supported by numerical experiments.  相似文献   

17.
In this article, a Crank‐Nicolson‐type finite difference scheme for the two‐dimensional Burgers' system is presented. The existence of the difference solution is shown by Brouwer fixed‐point theorem. The uniqueness of the difference solution and the stability and L2 convergence of the difference scheme are proved by energy method. An iterative algorithm for the difference scheme is given in detail. Furthermore, a linear predictor–corrector method is presented. The numerical results show that the predictor–corrector method is also convergent with the convergence order of two in both time and space. At last, some comments are provided for the backward Euler scheme. © 2008 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2009  相似文献   

18.
This paper is concerned with a compact difference scheme with the truncation error of order 3/2 for time and order 4 for space to an evolution equation with a weakly singular kernel. The integral term is treated by means of the second order convolution quadrature suggested by Lubich. The stability and convergence are proved by the energy method. A numerical experiment is reported to verify the theoretical predictions.  相似文献   

19.
本文在非一致时间网格上,使用有限差分方法求解变时间分数阶扩散方程?α(x,t)u(x,t)/tα(x,t)-2u(x,t)/x2=f(x,t),0α(x,t)q≤1,证明了该方法在最大范数下的稳定性与收敛性,收敛阶为C(Δt2-q+h2).数值实例验证了理论分析的结果.  相似文献   

20.
A finite difference scheme for estimating parameters in linear differential-delay equations is investigated. Convergence results and rates of convergence are obtained for a simple explicit (Euler's) method. Numerical examples are given to illustrate the convergence for the Euler method. Numerical results for a “higher order” scheme are also discussed.  相似文献   

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