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arXiv 1303.3769math.NAcs.NA
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泊松-能斯特-普朗克方程的守恒有限差分格式

A Conservative Finite Difference Scheme for Poisson-Nernst-Planck Equations

Illinois Institute of Technology(伊利诺伊理工学院);Rush University(鲁什大学);Pennsylvania State University(宾夕法尼亚州立大学)

Allen Flavell, Michael Machen, Bob Eisenberg, Chun Liu, Xiaofan Li

AI总结:

针对离子通道中的泊松-能斯特-普朗克方程,提出一种时空二阶精度的有限差分方法,通过简单迭代求解隐式离散非线性系统,并确保总离子守恒和能量耗散率正确。

摘要:

描述离子通道中离子传输动力学的宏观模型是泊松-能斯特-普朗克(PNP)方程。本文开发了一种求解PNP方程的有限差分方法,该方法在空间和时间上均具有二阶精度。我们使用专门适用于离子通道建模的物理参数。我们提出了一种简单的迭代方案来求解由时间隐式离散化产生的非线性方程组,该方案在几次迭代内收敛。我们强调确保数值方法具有与PNP方程本身相同的物理性质,即总离子守恒和正确的能量耗散率。我们详细描述了一种推导有限差分方法的方法,该方法精确地保持离子总浓度随时间不变。此外,我们说明,使用物理参数的实际值,守恒性质对于在长时间尺度上获得正确的数值解至关重要。

英文摘要:

A macroscopic model to describe the dynamics of ion transport in ion channels is the Poisson-Nernst-Planck(PNP) equations. In this paper, we develop a finite-difference method for solving PNP equations, which is second-order accurate in both space and time. We use the physical parameters specifically suited toward the modelling of ion channels. We present a simple iterative scheme to solve the system of nonlinear equations resulting from discretizing the equations implicitly in time, which is demonstrated to converge in a few iterations. We place emphasis on ensuring numerical methods to have the same physical properties that the PNP equations themselves also possess, namely conservation of total ions and correct rates of energy dissipation. We describe in detail an approach to derive a finite-difference method that preserves the total concentration of ions exactly in time. Further, we illustrate that, using realistic values of the physical parameters, the conservation property is critical in obtaining correct numerical solutions over long time scales.

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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