Heuristic modeling of material properties in Nano/Angstrom-scale channels: integrating experimental observations and MD simulations

Abstract

In this paper, we propose a unified framework to describe three key atomic-scale fluid properties-density, viscosity, and slip length-within nanoscale channels. These properties, which deviate significantly from bulk behavior, are expressed using simple power-law models as functions of the nanochannel height. The proposed framework accurately captures experimental and simulation data, providing a more flexible and interpretable alternative to existing complex or disparate models. The key advantage of our model lies in its mathematical properties. Continuity and a continuous derivative ensure seamless implementation into numerical simulations and theoretical predictions, leading to more understandable, stable, and accurate results. Additionally, the model adheres to physical principles, predicting convergence to bulk properties as channel size increases. Further, compared to existing exponential models, the unified power-law modeling approach offers several advantages. It provides flexibility by capturing nonlinear relationships and diverse data curvatures, interpretability through physically meaningful parameters, and adaptability for integration with other functions to model complex phenomena. Its simplicity facilitates easy parameter estimation, model interpretation, and computational efficiency. Moreover, its robustness makes it less sensitive to outliers and noise while maintaining fewer parameters that directly correspond to underlying physics and scaling laws. Hence, the proposed model’s simplicity, smoothness, physical validity, and generality establish it as a significant heuristic tool for the efficient design and optimization of nanoscale devices, utilizing theory and simulations across a wide range of applications.