Analysis of Film Boiling on Vertical Surfaces

Abstract

The two phase flow problem in laminar film boiling on a vertical flat plate is analyzed. The shear stress and vapor velocity at the vapor-liquid interface are taken into account. The problem is treated by solving simultaneously the boundary-layer equations for the vapor and liquid phases. In contrast to the film-condensation problem where the heat transfer is independent of the ρμ ratio, and where the interfacial shear can be neglected for a Prandtl number of unity or larger, it is shown that the ρμ ratio is an important parameter in the film-boiling heat transfer, and that the interfacial shear is quite different from zero.