Greg Ball, John Polansky, Tarik Kaya

Frontiers in Heat and Mass Transfer (FHMT) 4 - 013002 (2013)

The fluid flow and heat transfer in an evaporating extended meniscus are numerically studied.  Continuity, momentum, energy equations and the Kelvin-Clapeyron model are used to develop a third order, non-linear ordinary differential equation which governs the evaporating thin film.  It is shown that the numerical results strongly depend on the choice of the accommodation coefficient and Hamaker constant as well as the initial perturbations.  Therefore, in the absence of experimentally verified values, the numerical solutions should be considered as qualitative at best.  It is found that the numerical results produce negative liquid pressures under certain specific conditions. Although this suggests that the thin film can be in an unstable state of tension, this finding remains speculative without experimental validation.  Similar thin-film models proved to be very useful in gaining qualitative insight into the characteristics of evaporating thin films; however, the results shown in this study indicate that careful experimental investigations are needed to verify the mathematical models.