Evaporation from a two-dimensional meniscus

Evaporation from a two-dimensional meniscus, caused by the heating of a flat platinum plate immersed in a pool of water, is modeled and analyzed. Bernoulli's equation for incompressible inviscid fluid flow is applied to the meniscus line, which is approximated to be a streamline of the liquid flow. The effects on evaporation heat transfer of two types of resistance are examined parametrically: (1) that due to the evaporation coefficient at the liquid-vapor interface, and (2) that due to the presence of a nonevaporating thin film at the wall. A logarithmic coordinate transformation is used to stretch the region in the neighborhood of the wall, and the numerical results show that in this region the velocity at, and heat flux through, the meniscus line have maximum magnitudes. Using physically plausible values for resistance of the first type, the numerical results show that both the local and the total Nusselt number are insensitive to all physically plausible values for resistance of the second type. If, on the other hand, resistance of the first type is ignored altogether, serious errors arise in computed values for the Nusselt number.