The influence of mass transport on the heat transfer coefficients during the boiling of multicomponent mixtures

The paper describes a mathematical model of the process based on multicomponent mass transfer theory which enables the effect to be predicted of mass transport on the boiling heat transfer coefficient. The results of calculations were compared with our own experimental pool boiling data for the ternary system methanol-isopropanol-water and with Grigoriev's data obtained for the system acetone-methanol-water. The good accuracy was obtained when the ratio of the tube surface area to the surface area of the bubbles, which touch the heater at that moment, was considered as a parameter of the model. Based on our own experimental pool boiling data for the system methanol-isopropanol-water and the corresponding binary systems the triangular diagram of the ratio alpha(exp)/alpha(id) as a function of the liquid compositions is presented. (C) 2000 Editions scientifiques et medicales Elsevier SAS.