Abstract
As the development of laser technology, acoustic technology and weak signal detection technology, a new concept is put forward to solve the problem of measuring the concentration and distribution of water droplets in wet steam. The study presents the geometry of laser transfers in evaporating semitransparent water droplet in wet steam, analyzing the selective absorption of laser radiation and its influence on the evaporation processes. It's found that the evaporation of water droplets involve in advection, conduction, convection and mass transfer. In the series of physical process above, there are conversions of various energy, light energy, thermal energy and acoustic energy. The emergence of acoustic signal and mechanism of photoacoustic effect in water evaporation process are studied. The relation between droplet lifetime and evaporation rate is investigated. The distribution of temperature and pressure internal water droplet and its influence on evaporation process is indicated. The influence of laser intensity and wavelength and droplet initial state on evaporation process is investigated. In order to investigate the water droplet evaporation theoretically and numerically, it's necessary to simplify the single water droplet evaporation process by reasonable assumptions. The analysis of physical process of liquid saturated droplet evaporation in wet steam provides a certain theoretical basis for further quantitative study in the mechanism of droplet evaporation.
