UPPER AND LOWER BOUNDS OF DROPLET EVAPORATION IN 2-PHASE JETS

This paper examines the limits of evaporation of pure component droplets in two-phase jets emerging from the release of superheated liquids. Two models were developed based on mass, momentum, and energy balances. The first model is used for the calculation of the upper evaporation limit. This model assumes that the liquid droplets travel through stagnant atmospheric air with no back-pressure and with non-zero relative velocity. The second model is used for the calculation of the lower evaporation limit, assuming that the liquid droplets of the released material are carried along with the vapour phase and that there is no relative motion (zero relative velocity) between the phases. Uniform drop size and top-hat profiles (concentration, velocity, and temperature) are assumed. The effects of various parameters (i.e. droplet diameter, released material, superheat, etc.) on the evaporation bounds are revealed through parametric studies. The models' results are also compared with experimental data. Finally, recommendations for future work are given.