arXivDaily arXiv每日学术速递 周一至周五更新
arXiv周末暂无论文更新,休息一下吧,周末愉快~~
arXiv 1002.2925math.NAcs.NA
收藏

非线性奇异摄动方程差分格式的系数逼近构造

Construction Of Difference Schemes For Nonlinear Singular Perturbed Equations By Approximation Of Coefficients

Liudmila Rozanova

AI总结:

针对高阶导数含小系数的非线性奇异摄动问题,通过系数逼近方法构造了在指数和幂律边界层情形下一致收敛的差分格式。

摘要:

许多物理过程(如扩散、流体粘性和燃烧)的数学建模涉及高阶导数含小系数的微分方程。这些可能是模拟杂质扩散的小扩散系数、流体流动模拟中的小粘性系数等。解决此类问题的困难在于,如果将高阶导数的小参数设为零,退化问题的解即使在小参数趋近于零时也无法正确逼近原问题的解;原问题的解会出现边界层。因此,应用经典差分格式求解此类方程会产生很大误差。因此,数值求解高阶导数含小系数的微分方程需要特殊的差分格式,这些格式关于所涉及的小参数具有一致收敛性。本文作者研究了一个有限区间上的两个非线性边值问题,导致指数和幂律边界层。

英文摘要:

Mathematical modeling of many physical processes such as diffusion, viscosity of fluids and combustion involves differential equations with small coefficients of higher derivatives. These may be small diffusion coefficients for modeling the spreading of impurities, small coefficients of viscosity in fluid flow simulation etc. The difficulty with solving such problem is that if you set the small parameter at higher derivatives to zero, the solution of the degenerate problem doesn't correctly approximate the original problem, even if the small parameter approaches zero; the solution of the original problem exhibits the emergency of a boundary layer. As a result, the application of classical difference schemes for solving such equations produces great inaccuracies. Therefore, numerical solution of differential equations with small coefficients at higher derivatives demands special difference schemes exhibiting uniform convergence with respect to the small parameters involved. In this article author investigates two nonlinear boundary value problems on a finite interval, resulting in exponential and power-law boundary layers.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑