Abstract
Growth of ice crystals from the vapour phase generally occurs in three processes : volume diffusion process of water molecules, surface kinetic process characterized by the dependence on surface supersaturation of the kinetic coefficient and conduction process of the latent heat of sublimation. General expression for the growth rate of ice crystal is derived by taking into account these processes. This expression uses the supersaturation at infinite distance from the crystal surface to describe the macroscopic driving force for the growth and the sum of resistances for the individual processes. By estimating the values of the resistances, we can investigate the role of each process as rate determining process under the given growth conditions specified by temperature, supersaturation, crystal size, air pressure and so on. We also discuss the supersaturation determined by temperature and pressure of water vapour at the crystal surface under various growth conditions.
