Convective heat transfer characteristics of nanoconfined fluids with interfacial effects

With the miniaturization of thermal management systems, nanoscale convective heat transfer has become critical, yet classical continuum theories fail to capture interfacial discontinuous transport, leaving a gap in predicting nanoscale thermal performance. This work investigates interfacial transport phenomena in graphene nanochannels and develops a predictive theoretical model. Our results indicate that wall wettability significantly influences interfacial transport, governing both thermal slip and momentum slip by tuning solid-fluid interaction strength. Superhydrophilic conditions induce a Nusselt ( Nu ) number singularity, where the mean fluid temperature may exceed the wall temperature. Evaluations of flow, heat transfer, and comprehensive performance reveal that the superhydrophilic regime shows distinct evolutionary relationships compared to moderate and hydrophobic regimes, deviating from classical expectations. These results suggest that interfacial micro-mechanisms dominate over bulk fluid behavior under the studied conditions of nanoscale convective heat transfer. We derive a theoretical Nu model for fully developed convection by incorporating slip boundary conditions into the two-dimensional energy equation. This model quantifies wettability-modulated interfacial temperature jump length and heat transfer performance. This work clarifies the regulation mechanism of wettability on interfacial thermal transport in graphene nanochannels, and the developed Nu number model can provide a theoretical basis for the surface design of nanoscale thermal management devices.