Highly accurate simulation of electrokinetic transport processes in nanopores

纳米孔中动电传输过程的高精度模拟

• 批准号: 530066508
• 负责人: Dr.-Ing. Holger Marschall
• 金额: --
• 依托单位: Arbeitsgruppe Computational Multiphase Flow
• 依托单位国家: 德国
• 项目类别: Research Units
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/530066508?language=en
• 关键词: Highly; accurate; simulation; electrokinetic; transport

Subproject B3 is dedicated to the detailed modelling and highly accurate simulation of ion transport processes in transient nanopores under an applied potential. Thus, there is a direct link to the guiding experiment Electrically Modulatable Nanopores. The scientific focus of B3 is on the development of adaptive and hybrid approaches, which are particularly suitable to bridge the typically very different spatial and temporal scales in these transport processes and to numerically adequately implement the usually strong coupling between transport mechanisms. The central aim is to develop numerical methods of high numerical and physical fidelity for ion transport to produce physically accurate solutions. This is of high relevance, since classical measures of numerical fidelity (accuracy, stability, consistency) are not sufficient to address how well the system physics is represented by a particular numerical method. In practice, this is a surreptitious and subtle problem, since such a failure rarely causes outright abort of simulations due to instabilities, i.e., it can potentially go unnoticed leading to physically incorrect but converged results. This project will contribute to advancing the field of numerical methods and address the growing need for physically accurate solutions of ion transport processes in complex systems such as in transient nanopores under an applied potential. In particular, we will devise a hybrid atomistic-continuum (HAC) approach so as to couple molecular dynamics (MD) and continuum solvers, respectively. This enables a detailed computational analysis of ion transport processes close to the pore walls, where MD is used. Such an approach is particularly useful to examine transient pore systems where pure MD would be computationally prohibitive. As for the continuum solver, we will aim to implement most recent model formulations using improved closures to take into account effects like the finite size and solvation of ions in electrolytes. Moreover, a central objective is to develop a numerical method of high fidelity which accounts for the significant coupling between transport processes by means of an implicit simultaneous solution approach.

子项目B3致力于在应用电位下瞬态纳米孔中离子传输过程的详细建模和高精度模拟。因此，这与电可调纳米孔的指导实验有直接的联系。B3的科学重点是自适应和混合方法的发展，这些方法特别适合在这些运输过程中弥合典型的非常不同的空间和时间尺度，并在数值上充分实现运输机制之间通常很强的耦合。中心目标是发展高数值和物理保真离子传输的数值方法，以产生物理上精确的解决方案。这是高度相关的，因为传统的数值保真度度量（精度、稳定性、一致性）不足以解决系统物理如何很好地由特定的数值方法表示。在实践中，这是一个隐蔽而微妙的问题，因为这样的失败很少会由于不稳定而导致模拟的彻底中止，也就是说，它可能会被忽视，导致物理上不正确但收敛的结果。该项目将有助于推动数值方法领域的发展，并解决复杂系统中离子传输过程的物理精确解决方案日益增长的需求，例如在应用电位下的瞬态纳米孔。特别是，我们将设计一种混合原子-连续介质（HAC）方法，以便分别将分子动力学（MD）和连续介质求解器耦合起来。这使得可以对靠近孔壁的离子传输过程进行详细的计算分析，其中使用了MD。这种方法对于检测瞬态孔隙系统特别有用，因为纯MD在计算上是禁止的。至于连续介质求解器，我们的目标是实现最新的模型公式，使用改进的闭包来考虑诸如有限尺寸和电解质中离子的溶剂化等影响。此外，中心目标是开发一种高保真度的数值方法，该方法通过隐式同时求解方法来解释传输过程之间的重要耦合。