摘要
采用非等温DSC法,对过冷条件下水滴的液-固相变动力学特性进行了研究,获得了水滴结晶过程的速率常数、时间指数和Avrami指数。研究表明,降温速率对水的结晶行为影响较大。降温速率越大,则结晶速率越大,结晶峰温和结晶初始温度向低温方向移动,结晶的完善程度相对越差。在-40℃～0℃温度范围,水滴的结晶以异相成核的三维球晶方式生长。
The non-isothermal crystallization behavior and kinetics of supercooled water droplets were investigated by means ot me differential scanning calorimetry （DSC） method and the rate constant, time index and Avrami index of crystallization were obtained. The results show that the cooling rate has great influence on the crystallization behavior of water. The crystallization rate increases and the initial temperature and peak temperature of crystallization decrease with the increase of the cooling rate. In the temperature range of-40℃-0℃, the crystallization exhibits three-dimensional spherulitic growth on heterogeneous nuclei.
出处
《制冷学报》
CAS
CSCD
北大核心
2008年第4期30-33,共4页
Journal of Refrigeration
基金
国家自然科学基金资助项目(10672174)~~
关键词
工程热物理
过冷水滴
液-固相变
DSC法
结晶
动力学
Engineering thermophysics
Supercooled water droplets
DSC method
Liquid-solid phase change
Crystallization
Kinetics
