Impact of silver nanofluid modifications on heat pipe thermal performance

Abstract

This study investigates thermal performance enhancement in heat pipes using surface-modified silver nanofluids, addressing the limitations of traditional working fluids in thermal conductivity and heat transfer. The primary objective of this study is to investigate the impact of surface-modified silver nanofluids on the thermal performance of heat pipes. While previous research has explored the use of nanofluids to enhance thermal conductivity, this study introduces a novel approach by utilizing three distinct surface modifications: branched polyethyleneimine, methoxy polyethylene glycol 5 kDa, and aminated silica shells. The innovative combination of a silver core with these specific surface modifications, particularly the aminated silica shell, represents a significant advancement in the field, leading to unprecedented enhancements in thermal conductivity, thermal resistance, and heat transfer rates. Characterization was performed using transmission electron microscopy, zeta potential analysis. Thermal performance was evaluated in a custom-designed heat pipe system, and the key results showed that silica-shelled nanofluids exhibited the highest thermal conductivity, increasing by 10%, and the lowest thermal resistance, reducing by 35%. These nanofluids also achieved the highest heat transfer coefficients, improving by 25%, and the highest heat transfer rates increased by 30%. Conclusions indicate that surface modifications significantly enhance the thermal properties of nanofluids, making them suitable for advanced thermal management applications. The novelty of this work lies in its comprehensive analysis, revealing that aminated silica shells provide superior thermal performance. This study quantitatively demonstrates specific improvements in thermal conductivity, thermal resistance, heat transfer coefficients, and rates, suggesting that surface-modified nanofluids can significantly enhance the performance of thermal systems such as heat pipes and cooling systems, offering substantial benefits in various engineering applications. This research addresses the critical gap in understanding how surface modifications influence nanofluid stability and performance, offering new insights into optimizing heat transfer fluids for advanced thermal management systems.