Molecular dynamics investigation of the slip flow liquid–solid interfacial thermal conductance

Abstract

With the integrated high-power device packaging structure rapidly developing, the embedded heat dissipation architectures are challenged by the local micro-/nanoscale massive heat flux. The slip flow molecular dynamics models were established to explore the liquid–solid interfacial thermal conductance. With stepwise declining shear forces (0.032 pN/200, 0.024 pN/200, and 0.016 pN/200 ps, respectively), the slip flow [the slip shear velocity is Si: (125.43 ± 0.92 m/s), graphite: (142.43 ± 1.92 m/s), and Cu: (180.93 ± 3.42 m/s), respectively] water–solid interfacial thermal conductance of different materials [Si: (8.11 ± 0.1) × 107 W/m2 K, graphite: (10.18 ± 0.1) × 107 W/m2 K, and Cu: (17.97 ± 0.1) × 107 W/m2 K] can be calculated. The rationality of the calculated values can be verified in the literature. The slip flow water–solid interfacial thermal conductance values are about 0.5 times higher than the static ones. It can be significantly affected by the slip shear velocity. The slip shear velocity increasing about five times can enhance the interfacial thermal conductance two times. From the water layer density distribution, it is found that the dependence of interfacial thermal conductance on velocity slip relies more on the dynamical properties than on the fluid structure. This molecular dynamics model provides an operative methodology to investigate the slip flow liquid–solid interfacial heat transfer for the various embedded cooling surfaces.