Molecular dynamics simulation of heat transfer trough interface between rough walls

Non-equilibrium molecular dynamics simulation is carried out to study the effects of wettability and nanoscale roughness on heat transfer through the solid-liquid interface. The liquid is Ar and the solid wall is Pt. The roughnesses with different shapes, including triangular, rectangular, sinusoidal and random roughnesses, distribute on the walls. The two walls are kept at different temperature by the phantom method. The USHER algorithm is employed to maintain an identical liquid density. The results show that (1) Both the wettability and the roughness can reduce the interfacial thermal resistance, thus enhancing the heat transfer through the interface by increasing the contact area; (2) The roughness shapes have effects on the heat transfer and the rectangular roughness performs best in enhancing heat transfer; (3) Both of the wettability and roughness have little effects on the film conduction, and the interfacial thermal resistance is found to be the key factor that influences heat transfer.