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arXiv 1708.09446math.NAcs.NA
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一种非散度形式的二阶多尺度超几何问题的方程自由方法

An Equation-Free Approach for Second Order Multiscale Hyperbolic Problems in Non-Divergence Form

École Polytechniques Fédérale de Lausanne(洛桑联邦理工学院);Uppsala University(乌普萨拉大学)

Doghonay Arjmand, Gunilla Kreiss

AI总结:

本文提出了一种方程自由方法,用于非散度形式的二阶超几何方程的数值均质化,通过在多尺度设置中近似粗尺度行为,以避免对小尺度的高成本模拟。

摘要:

本文研究了非散度形式的二阶超几何方程的数值均质化,其中模型问题包含快速振荡的系数函数。这些小尺度影响大尺度行为,因此在数值模拟中必须准确建模其影响。直接数值模拟成本过高,因为至少需要每个波长两个点来解析小尺度。本文提出了一种多尺度方法,在方程自由方法下,以与问题中的小尺度无关的成本近似精确解的粗尺度行为。我们证明了在单变量和多变量周期设置中,放大量的收敛率。此外,提供了一维和二维的数值结果以支持理论。

英文摘要:

The present study concerns the numerical homogenization of second order hyperbolic equations in non-divergence form, where the model problem includes a rapidly oscillating coefficient function. These small scales influence the large scale behavior, hence their effects should be accurately modelled in a numerical simulation. A direct numerical simulation is prohibitively expensive since a minimum of two points per wavelength are needed to resolve the small scales. A multiscale method, under the equation free methodology, is proposed to approximate the coarse scale behaviour of the exact solution at a cost independent of the small scales in the problem. We prove convergence rates for the upscaled quantities in one as well as in multi-dimensional periodic settings. Moreover, numerical results in one and two dimensions are provided to support the theory.

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。

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