Evaporation of ice droplet

• 主要作者: Ng, Say Chong.
• 其他作者: School of Mechanical and Aerospace Engineering
• 格式: Final Year Project
• 語言: English
• 出版: 2012
• 主題: DRNTU::Engineering::Mechanical engineering
• 在線閱讀: http://hdl.handle.net/10356/49657

Sublimation of a substance is the process of transitioning from solid phase to vapor phase. Despite the common occurrence of sublimation, the process is still not predictable up till this date. A theoretical approach based on the transition probability concept of quantum mechanics and Boltzmann deification of entropy, called Statistical Rate Theory (SRT) has been used to investigate the evaporation process of liquids. Previous studies had shown that this model predicted the conditions for evaporation of water and heavy water at spherical and cylindrical interfaces very well. Hence the application of SRT is to extend further to study the sublimation of ice. In this project, a series of experiments were designed and conducted on an approximate spherical ice droplet to obtain the parameters for SRT prediction. The experiments were carried out over a range under triple point pressure of 611pa necessary for sublimation to take place. It is found that measured and predicted values agree with each other. Throughout the experiment, unexpected difficulties were encountered and modifications to improve the experiment were proposed. For future work, it is suggested that nano-filtered water or pure ethanol can be applied in the experiments.