Mass and heat transfer resistivities at liquid–vapor interfaces: Beyond the ideal gas

The classical Hertz–Knudsen–Schrage (HKS) model for non-equilibrium mass and heat transfer across liquid–vapor interfaces is extended to account for real gas effects and non-linearity. Specifically, the HKS relations are re-derived for a temperature and velocity dependent condensation coefficient (Tsuruta et al., 1999) and combined with real gas property relations derived from the Enskog–Vlasov (EV) equation (Struchtrup and Frezzotti, 2022). The resulting non-linear Tsuruta–EV–HKS model is valid for mass and heat transfer up to the critical point. The resulting interfacial resistivities exhibit marked dependence on temperature, with resistivities strongly decreasing towards the critical point, as well as non-linear dependence on mass and heat flux. • Hertz–Knudsen–Schrage model extended to real gas vapors and non-linear transport. • Evaporation and heat transfer resistivities vanish towards the critical point. • Non-linearities affect interface resistance. • Molecular Dynamics simulations show similar trends. • Marked temperature dependence and non-linearity affect experiments and simulations.