| Abstract [eng] |
Dissertation investigates the complex processes of water droplet heat and mass transfer. They are combined in a cycle of condensing, transitional evaporation and equilibrium evaporation regimes during the phase change which occurs on a droplet’s surface. The dynamics of a heated droplet’s surface temperature is directly related to the regimes. Stefan’s hydrodynamic flow influence is evaluated by the similarity theory based Spalding transfer parameter and its extension for the whole droplet phase transformation cycle is provided. The presented mathematical model and its development, as well as the numerical solution algorithm, do not contradict for provided droplet physical interpretation in the work which includes a droplet’s geometrical, thermal and energy state analysis. The definition of the flux dynamics near the droplet’s surface is based on a numerical iterative scheme which depends on the balance of the heat fluxes on the droplet’s surface. In the iterative scheme, the optimal parameters are outlined. In this scheme, the energy of the phase change and the external heat transfer are combined as well as the internal heat transfer which takes place in droplets. The results of the modeling conducted in this dissertation allow to achieve better understanding of complex transfer process in a consistently changing cycle of droplet phase transformation regimes. They also show the impact of radiation on the droplet’s thermal state and on the transitional evaporation regime. |
