Evaluation of overshooting errors in particle methods for diffusion by biased global random walk
Evaluation of overshooting errors in particle methods for diffusion by biased global random walk
复制标题
通过偏置全局随机游走评估扩散粒子方法中的超调误差
DOI：
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发表时间：
2006
期刊：
影响因子：
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通讯作者：
C. Vamos
中科院分区：
文献类型：
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作者：
N. Suciu;C. Vamos
为了保证粒子法不产生数值扩散，网格步长的调整不可避免地会导致空间变系数抛物型偏微分方程解的超调误差。在本文中，我们对“全局随机游走”算法（GRW）的超调误差进行了评估，该算法是一种用于环境问题运输模拟的计算有效方法。评估是通过比较 GRW 解决方案和“有偏全局随机游走”算法 (BGRW) 的解决方案来进行的，后者是一种元胞自动机，其计算成本更高，但也不存在超调误差。参考问题是随机速度场中的扩散传输，这是地下水中污染物溶质传输的模型。评估表明，对于参数的最佳选择，实际感兴趣的时间间隔的 GRW 结果位于可接受的精度范围内，对于系综平均可观测量及其波动而言。
The adjustment of grid steps which guarantees that particles methods yield no numerical diffusion inevitably induces overshooting errors in the solution of the parabolic partial differential equations with space variable coefficients. In this paper we give an evaluation of the overshooting errors of the "global random walk" algorithm (GRW), a computational efficient method used in simulations for transport in environmental problems. The evaluation is performed by comparisons between the GRW solutions and those of the "biased global random walk" algorithm (BGRW), a cellular automaton, which is computationally more expensive but is also free of overshooting errors. The reference problem was the diffusive transport in a random velocity field, a model for the transport of the contaminant solutes in groundwater. The evaluation reveals that, for an optimum choice of the parameters, GRW results for time intervals of practical interest lie in ranges of acceptable precision, for both the ensemble averaged observables and for their fluctuations.
非均质含水层溶质输运遍历性的数值研究
影响因子：
5.4
作者：
Suciu N.. C. Vamos;J. Vanderborght. H. Hardelauf;H. Vereecken (2006).
通讯作者：
H. Vereecken (2006).