Interfacial models for the critical heat flux superheat of a binary mixture

摘要

A constant partial vapor pressure model for surface shear in a two-component evaporating thin film is used to successfully predict previously published data on the effect of cooncentration and pressure on the superheat at the critical heat fluxs. Due to the dynamics of the high flux interfacial molecular processes, a small portion of the interface can be modeled using a constant partial vapor pressure boundary condition with a varying temperature and concentration in the liquid. This boundary condition demonstrates that, when a distilling fluid with a high initial concentration of the more volatile component flows towards a hotter contact line, the surface shear stress can change sign. Therefore, depending on the details of the distillation process in the microlayer-contact line region, enhanced flow can change to inhibited flow.