水平冷表面上结霜发生随机性研究

STUDY ON THE RANDOMNESS OF FROST FORMATION ON A COLD FLAT SURFACE

水蒸气在冷壁面上的结霜是制冷、低温领域普遍存在的问题。过饱和的水蒸气有两种相变途径 ,一种是气液固相变 ;一种是直接气固相变。气液固相变经历气液相变和液固相变两个阶段 ,实验研究表明其发生具有随机性。在前人实验研究的基础上 ,从理论上给出了液珠半径随时间的增长规律 。

Frosting on a cold surface is a common phenomenon in cryogenic fields.There are two paths of phase change for supersaturation vapor,one of which is vapor liquid solid phase change and the other is directly vapor solid phase change.The phase change of vapor liquid solid can be divided into two steps:vapor liquid phase change and liquid solid phase change.This whole process of vapor liquid solid phase change happens with randomness,which was indicated by former experimental observations.Based on the available experimental result,this paper developed a formula to describe the growth of liquid drop radius with time and furthermore studied the randomness of frost formation on a cold surface under the natural convection condition.