Evaporation Characteristics of Heat Pipes with Sub-Critical Nanopores

TL;DR

This study uses molecular dynamics simulations to analyze heat transfer in nanoporous heat pipes, revealing how pore size, temperature gradients, and fill ratios influence efficiency, with implications for nanoscale thermal management.

Contribution

It provides new insights into heat transfer mechanisms in nanoporous heat pipes at the nanoscale, highlighting the effects of pore size and surface-driven flows.

Findings

Larger temperature gradients improve heat transfer rates.

Filled heat pipes outperform medium-filled ones.

2 nm nanopores show better performance than 3 nm ones.

Abstract

This study explores heat transfer mechanisms in heat pipes with sub-critical nanopores using coarse-grained molecular dynamics (CGMD) simulations, aiming to enhance thermal management in nanoscale applications. With the increasing need for efficient cooling solutions in microelectronics and high-performance computing, nanoporous heat pipes have gained attention due to their high thermal conductivity and passive operation. This research evaluates the effects of pore size, temperature gradients, and water fill ratios on the heat transfer efficiency of heat pipes with 2 nm and 3 nm diameter nanopores. The results indicate that larger temperature gradients significantly enhance heat transfer rates, while filled heat pipes perform better than medium-filled ones, primarily due to more effective phase change and fluid flow dynamics. Notably, the 2 nm filled models show improved performance over the 3 nm models, suggesting an optimal balance between capillary action and fluid resistance at smaller pore sizes. The study also reveals that in sub-critical nanopores, surface-driven flows are more effective than traditional wicking, underscoring the role of surface interactions in optimizing heat transfer. These findings provide critical insights for designing and optimizing nanoporous heat pipes, offering practical guidance for developing more efficient thermal management systems in electronics cooling and other applications.