Rapid boiling of ultra-thin liquid argon film on patterned wettability surface with nanostructure: A molecular dynamics investigation

Surface wettability and structure have been proved as two important influential factors to the thermal transport at the solid-liquid interface at nano scale, however, the combined enhancement mechanism has not been clearly understood till now. In this study, the rapid boiling behaviors of nano thin liquid argon film on the heterogeneous wetting surfaces were examined with the non-equilibrium molecular dynamics (MD) method. Meanwhile, the ring-patterned and stripe-patterned surfaces were designed and analyzed, respectively. By analyzing the trajectory of argon atoms, the bubble nucleation behavior, heat flux and interfacial thermal resistance, it is found that the lower hydrophobic area fraction is favorable for the bubble formation and the ring-patterned surface shows an advantage in the nucleate boiling compared with the stripe-patterned one. Meanwhile, the nanostructure has a great influence on the boiling phenomena, which accelerates the development of bubble nuclei and improves the maximum heat flux compared with the planar one. In present simulations, the ring-patterned surface with nanostructure of 40% hydrophobic area fraction is the optimal design for the efficiency enhancement of explosive boiling process. The findings in this work contribute to the design of the coating nanostructured surface to enhance the boiling heat transfer performance under the high heat fluxes.