Nanoscale inter-groove coupling governs cooperative boiling nucleation: A molecular dynamics study

Molecular dynamics simulations were performed to investigate nanoscale boiling behaviors on surfaces with single- and double-groove geometries. By analyzing the temporal evolutions of temperature, density, kinetic and total energy, heat flux, and vapor atom population, this study identifies a previously uncharacterized nanoscale inter-groove coupling mechanism that governs bubble nucleation and growth. Adjacent grooves interact thermally and hydrodynamically, leading to nearly synchronized nucleation, faster liquid film thinning, and cooperative bubble coalescence. Such coupling promotes localized energy accumulation and the formation of a continuous vapor energy region between grooves, thereby enhancing interfacial heat transfer. The observed “double-groove effect” manifests as reduced nucleation delay and intensified energy activity near the wall. These findings provide molecular-level insight into cooperative groove interactions and establish a mechanistic foundation for designing multi-groove boiling surfaces with coupled micro/nanostructures.