Analysis of laminar film boiling in boundary layer flows with appreciable radiation

Abstract

This paper presents the theoretical study of the heat transfer and friction characteristics in the natural convection film boiling on an inclined surface and a sphere, the forced convection film boiling over a horizontal plate, and the stagnation flow film boiling when radiation is appreciable. The boiling liquid is either at the saturation temperature or subcooled. The two phase flow and heat transfer problems have been formulated exactly within the framework of boundary layer theory with the consideration of the shear stress and vapor velocity at the liquid-vapor interface. Through the use of the similarity transformation expressions are obtained to determine the vapor film thickness, skin friction, and heat transfer rate. It is disclosed that the presence of surface radiation results in an increase in the heat transfer rate and a decrease in the skin friction.