Temperature and heat flux dependence of thermal resistance of water/metal nanoparticle interfaces at sub-boiling temperatures

Molecular dynamics simulations of heat transport through nanoscale metallic systems in contact with water are performed to investigate the effects of temperature and heat flux on thermal resistance across the interface. Non-equilibrium MD simulations are performed using 4 different metals: gold, silver, copper, and aluminum. The simulation space is composed of a 5-nm wide nanochannel of water between two parallel metallic walls, with one wall serving as a heat source and the second serving as a heat sink. 60 simulations are performed at heat source temperatures spanning from 300 K to 650 K at intervals of 25 K, and fixed heat sink temperatures of 250 K. Steady-state wall and fluid temperatures at the interfaces and the imposed energy required maintaining each wall temperature are recorded to measure system heat flux. The interfacial thermal resistance is calculated for each wall temperature and metal combination, and the wall temperatures, heat fluxes, and resistance data is presented for all cases where the interfacial water temperature is below 373 K. Using two-dimensional least squares regression, linear fit coefficients for the calculation of interfacial thermal resistance as a function of wall temperature and heat flux are compiled. These fitting coefficients may be used to implement temperature and heat flux-dependent interfacial resistances for each metal for a variety of thermal applications.