Application of nanofluids in heat pipes

Nanofluids can effectively enhance the heat transfer performance of different types of heat pipes according to the existing research. This paper provides a comprehensive literature review on the application of nanofluids in thermosyphon heat pipe, pulsating heat pipe and wick heat pipe, respectively. The effect of important variables such as different nanoparticles, concentrations, packing ratios, inclination angles and thermal loads on heat pipe performance is discussed. Studies shows that there is a certain concentration of nanoparticles for highly efficient utilization. High concentration of nanoparticles leads to higher thermal resistance mainly due to the increase in dynamic viscosity and the possibility of particle agglomeration. The enhanced heat transfer performance is caused by the enhanced Brownian motion, improved surface wettability, increased nucleation sites and inherently high thermal conductivity of nanofluids. Finally, the current problems and future trends of heat pipe technology based on nanofluids are discussed.