CONDENSATIONAL DROPLET GROWTH IN THE CONTINUUM REGIME - A CRITICAL-REVIEW FOR THE SYSTEM AIR-WATER

Condensational droplet growth in the system water vapour-air is investigated. A rigorous theoretical consideration based on the complete first-order transport equations for heat and mass is performed. Stefan-flow, thermal diffusion and Dufour effect thus are included in the consideration. Not only the temperature dependence of the transport coefficients but also their dependence on the composition of the system is taken into account. On the basis of the complete equation for heat transport a temperature profile is derived. With this temperature profile the mass flux caused by thermal diffusion is calculated. By results of numerical calculations it is shown if a rigorous consideration is required for practical calculations of droplet growth in the system water vapour-air. The results of Kulmala and Vesala given for the case of assuming the enthalpy of the vapour and the thermal conductivity as functions of the temperature and taking into account the Dufour effect have been corrected. An approximate calculation is performed to determine the thermal diffusion factor.