Molecular dynamics simulation on boiling heat transfer characteristics of nanostructured–liquid metal coupled surfaces

In order to investigate the mechanisms by which liquid metal modulates and enhances boiling heat transfer on nanostructured surfaces, MD simulations were performed to systematically examine the coupling effects of copper nanopillar height and gallium (Ga) layer thickness on the boiling behavior of water films. The results indicate that expanding the solid–liquid contact area and lowering the energy barrier for bubble nucleation enable nanopillar configurations to promote earlier bubble nucleation and quicker bubble growth. Nanopillars with a height of 35 Å deliver the strongest enhancement, raising the peak heat flux by up to 71% and improving the heat transfer coefficient by as much as 33.9%, while also promoting faster energy accumulation in water molecules and accelerating the phase-change process. The thickness of the liquid gallium layer is another factor that cannot be overlooked in interfacial heat transfer. An optimal balance among interfacial thermal resistance, capillary driving force, and atomic mobility is achieved when the gallium layer is 10 Å thick, giving the lowest interfacial thermal resistance (8.60 × 10⁻⁹ m²K/W) and the highest average heat transfer coefficient (7.42 × 10 −6 eV/(Å 2 ·ps·K)) during the early stage of boiling (first 450 ps). This combination, by optimizing the surface microstructure and introducing high-performance thermally conductive materials, provides new insights for solving heat dissipation challenges in high-temperature devices.