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arXiv 1509.04567math.NAcs.NA
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时间并行Paraexp方法的块Krylov子空间实现及其在非线性偏微分方程中的扩展

A Block Krylov Subspace Implementation of the Time-Parallel Paraexp Method and its Extension for Nonlinear Partial Differential Equations

University of Twente(特温特大学);Eindhoven University of Technology(埃因霍温理工大学)

G. L. Kooij, M. A. Botchev, B. J. Geurts

AI总结:

本文提出了一种用于非线性偏微分方程的时间并行积分方法,基于块Krylov子空间方法改进的Paraexp方法,并在波形松弛框架下应用于非线性问题,通过超位置原理将问题分解为独立子问题,利用指数积分快速求解。

摘要:

本文提出了一种用于非线性偏微分方程的时间并行积分方法。该方法基于一种新的Paraexp方法的实现,该方法用于线性偏微分方程,采用块Krylov子空间方法。对于非线性PDEs,该算法基于在波形松弛框架内的Paraexp实现。初始值问题通过在完整时间区间上迭代求解。非线性项被作为源项处理,由前一次迭代的解提供。在每次迭代中,通过超位置原理将问题分解为独立的子问题。这些解耦的子问题通过基于块Krylov方法的指数积分快速求解。新的时间积分方法在一维对流扩散方程和粘性Burgers方程上进行了演示。数值实验证实了对于线性对流扩散问题具有优异的并行扩展性,并在模拟非线性Burgers方程时表现出良好的扩展性。

英文摘要:

A parallel time integration method for nonlinear partial differential equations is proposed. It is based on a new implementation of the Paraexp method for linear partial differential equations (PDEs) employing a block Krylov subspace method. For nonlinear PDEs the algorithm is based on our Paraexp implementation within a waveform relaxation. The initial value problem is solved iteratively on a complete time interval. Nonlinear terms are treated as a source term, provided by the solution from the previous iteration. At each iteration, the problem is decoupled into independent subproblems by the principle of superposition. The decoupled subproblems are solved fast by exponential integration, based on a block Krylov method. The new time integration is demonstrated for the one-dimensional advection-diffusion equation and the viscous Burgers equation. Numerical experiments confirm excellent parallel scaling for the linear advection-diffusion problem, and good scaling in case the nonlinear Burgers equation is simulated.

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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