Open Access

ARTICLE

Heat Transfer across Nanoscale Solid-Fluid-Solid Nanogaps: Effects of Interfacial Wettability, Wall Temperature, and Channel Height

Chenyang Sun¹, Wenke Zhao^2,*, Xiaoyuan Li^1,*, Jian Liu³
1 Institute of Machinery Manufacturing Technology, China Academy of Engineering Physics, Mianyang, China
2 School of Energy Science and Engineering, Harbin Institute of Technology, Harbin, China
3 School of Transportation and Vehicle Engineering, Shandong University of Technology, Zibo, China
* Corresponding Author: Wenke Zhao. Email: ; Xiaoyuan Li. Email:
(This article belongs to the Special Issue: Heat Transfer and Thermal Management in Renewable Energy Systems)

Energy Engineering https://doi.org/10.32604/ee.2026.086173

Received 25 May 2026; Accepted 14 July 2026; Published online 31 July 2026

Abstract

Using non-equilibrium molecular dynamics (NEMD) simulations with an imposed temperature gradient, we systematically investigate the heat flux and interfacial thermal resistance (ITR) of solid-liquid interfaces in liquid-filled nanogaps. The effects of interfacial wettability, wall temperature, and channel height on heat transfer characteristics in the present system are comprehensively analyzed. Potential of mean force (PMF) and vibrational density of states (VDOS) at the interface are employed to elucidate the underlying mechanisms of interfacial adsorption and heat transfer. Our simulations demonstrate that strongly attractive walls can significantly enhance system heat transfer, reducing the ITR to a negligible level relative to the bulk fluid thermal resistance. Furthermore, within the studied temperature range, the temperature dependence of ITR is found to be strongly correlated with interfacial wettability. Specifically, under weak wettability conditions, ITR shows no direct correlation with the absolute temperature of individual walls within the investigated interval; instead, it correlates with the arithmetic average temperature of the two walls or the average fluid temperature. Additionally, the heat flux in nanogaps exhibits a pronounced dependence on channel height when interfacial wettability is strong. These findings provide valuable theoretical insights for the design of advanced thermal management devices for high-power electronic systems.

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Keywords

Heat transfer; molecular dynamics simulation; heat flux; interfacial thermal resistance

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