Abstract
Forced convection heat transfer experiments of a liquid-gas foam were conducted by using a heated circular cylinder. In the temperature range around 373K, the heat flux for the foam flow is greater then that for water. In other temperature ranges, the heat flux for foam flow is lower than that of water. The heat transfer coefficient increases with increasing foam velocity and with decreasing the expansion ratio of the foam. It was indicated that the value of the coefficient greatly increases when the temperature of the heating surface approaches to 373K. Latent heat transfer by water vapor diffusion in the foam is the one of the important factors that increases the heat transfer coefficient near the boiling point of the foam.
