Continuum Modeling of Ultrafast Water Flow in Carbon Nanotubes Informed by Molecular Dynamics Studies

Water transport within carbon nanotubes (CNTs) exhibits unique characteristics due to nanoscale confinement and ultrasmooth hydrophobic interfaces, posing significant challenges for accurate modeling. This study presents a molecular dynamics (MD)-calibrated continuum model for predicting ultrafast water flow in CNTs. By integrating MD-derived slip length and viscosity parameters into a continuum framework, we achieve high-fidelity predictions of water transport, accurately capturing pressure drops, entrance resistance, and significant flow rate enhancements. This approach offers a computationally efficient alternative to direct MD simulations, reducing the computational cost by orders of magnitude while maintaining the accuracy. Importantly, this methodology is not limited to water transport in CNTs. Our MD-calibrated continuum model integrates validated MD-derived parameters into a finite element framework, enabling efficient micrometer-scale CNT simulations without new MD simulations. It provides a generalized framework for accurately modeling fluid transport in confined systems where nanoscale phenomena significantly deviate from classical fluid mechanics. By calibrating continuum models with molecular-level simulations, we can extend this approach to other fluids and nanostructured materials, enabling the design and optimization of advanced nanofluidic devices and systems.