过冷却器结冰影响机制的实验研究

Experimental Study on the Influence Mechanism of Icing in Supercooler

摘要:

从经典形核理论入手分析了过冷却器结冰的影响因素。在此基础上，搭建了过冷法制备冰浆实验台，通过大量实验对过冷水在过冷却器内结冰过程展开研究，结合边界层理论初步探究了流动与换热过程对过冷却器结冰的影响机制。实验结果表明：过冷水形核过程受换热壁面温度与流体扰动的共同影响；当Re数较小或二次冷媒温度较低时的形核主要受换热壁温影响；当Re数较大时的形核主要受到流体扰动的影响。

Abstract:

The factors that affect the freezing process in supercooler was analyzed based on the classical nucleation theory in this paper. Then, the experiment bench which is used to make ice slurry by supercooled method were set up to research the freezing process in the supercooler. The impact mechanism of flow and heat transfer process to freezing in supercooler was explored preliminarily combining with the theory of boundary layer. The experimental results show that the supercooled water nucleation process is influenced mutally by the heat transfer surface tempeature and the disturbance of fluid. The nucleation is mainly affected by heat transfer wall temperature when the Re number is small or the temperature of secondary refrigerant is low and is mainly affected by the fluid disturbance when the Re number is large.