Interfacial engineering-mediated heterogeneous nucleation and thermal transport for dielectric fluid

Mitigating the high-flux waste heat is essential and challenging to industrial applications such as artificial intelligence and high-power devices. Boiling heat transfer which combines convection with phase-change is promising for high heat-flux cooling. Despite extensive research, systematic understanding of bubble nucleation and thermal transport mechanisms is seemingly unresolve yet because the evaporative mass transfer is highly affected by microlayer at extremely small spatial-temporal scales. This occurs in a system highly dependent on interfacial properties like intermolecular interactions and heat carrier transport characteristics, which are currently difficult to reveal through experimental observations. In this study, the underlying influences of interfacial wetting and functionalized surfaces on heterogeneous boiling of dielectric fluid R1336mzz(Z) are comprehensively varied and examined from molecular dynamics viewpoint. Results reveal that the occurrence of nanobubble embryos has a trade-off relationship between thermal transport and potential energy barrier under different wetting conditions. Even though dielectric fluids show highly wettable property under macro conditions, further increasing solid-liquid interactions can still significantly improve boiling heat transfer performance before energy coefficient reaches 1.75. Additionally, introducing the self-assembled monolayer as an intermediate buffer shows to superior boiling performance than nonchemically planar interfaces through collaboratively modifying the interatomic interaction energy and bridging the vibration spectrum across interfaces. These findings elucidate the physical mechanism behind thermal transport in heterogeneous nucleation and also shed light on interfacial tailoring for boiling heat transfer enhancement.