从受限流体的分子涨落中解析时空耦合输运
Resolving coupled transport in space and time from molecular fluctuations in confined fluids
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中文总结 AI 辅助
该研究将纳米受限流体的耦合输运构建为时空分辨的Onsager响应矩阵，通过平衡态分子动力学模拟提取，解析了受限带电流体中多类输运的非局域与瞬态路径，为相关输运定律提供微观基础。
中文摘要 AI 辅助
流体中的输运通常简化为由体相系数和有效界面参数（如粘度、扩散系数、滑移长度及界面阻力）参数化的连续介质定律。该描述在纳米尺度下不再完整，此时空间异质性、分子结构与有限弛豫时间均与输运过程不可分割。本文将纳米受限流体中的耦合输运构建为时空分辨的Onsager响应矩阵，并从平衡态分子动力学模拟中提取该矩阵。将该框架应用于受限带电流体时，可解析耦合粒子、溶质、热量与电荷输运的非局域及瞬态路径：动量输运表现为长寿命的非局域流体力学模式，而电荷输运则通过局域化离子摩擦快速弛豫；非对角响应揭示了不同的投影动力学，为非局域、依赖历史的输运定律提供了微观基础。
英文摘要
Transport in fluids is generally reduced to continuum laws parametrized by bulk coefficients and effective interfacial parameters, such as viscosities, diffusivities, slip lengths, and interfacial resistances. This description becomes incomplete at the nanoscale, where spatial heterogeneity, molecular structure, and finite relaxation times are inseparable from the transport process. Here we formulate coupled transport in nanoconfined fluids as a space--time-resolved Onsager response matrix and extract it from equilibrium molecular dynamics simulations. Applied to a confined charged fluid, the framework resolves the nonlocal and transient pathways coupling particle, solute, heat, and charge transport. Momentum transport appears as a long-lived, nonlocal hydrodynamic mode, whereas charge transport relaxes rapidly through localized ionic friction. Off-diagonal responses reveal distinct projected dynamics, providing a microscopic basis for nonlocal, history-dependent transport laws.
