Numerical analysis of single bubble departure from a heated surface

Numerical analysis has been performed on bubble growth and departure from a heated surface in order to elucidate the mechanism of nucleate boiling heat transfer. Transient Navier-Stokes and energy equations were solved simultaneously both for liquid and vapor phases. Evaporation at the liquid-vapor interface was taken into account. We made use of an improved VOF(Volume of Fluid) method to trace the shape of bubble. A single bubble of helium on a flat surface and in a cavity under atmospheric pressure has been simulated. The temperature distribution obtained is quite similar to the photograph of thermal boundary layer. Velocity vectors inside and outside of the bubble and the dirtribution of the Nusselt number on the heat transfer surface are obtained. Change of the bubble radius with time almost agrees with those by previous studies([6]-[12]).