超临界CO_2迅速降压过程的亚稳成核机理研究  

RESEARCH ON METASTABLE CHARACTERISTICS AND NUCLEATION MECHANISM IN THE RAPID DEPRESSION PROCESS OF SUPERCRITICAL CO_2 FLUID

作　　者：马一太[1] 管海清[1] 曾宪阳[1] 

机构地区：[1]天津大学热能研究所,天津300072

出　　处：《工程热物理学报》2006年第2期208-210,共3页Journal of Engineering Thermophysics

基　　金：国家自然科学基金资助项目(No.50476060)

摘　　要：本文对超临界CO2流体迅速降压过程的热力学机理方面进行探讨。对迅速降压中的CO2的亚稳态平衡特性进行分析,研究CO2过热液的成核机理。计算结果表明:在迅速降压过程中,CO2气化核心的临界半径和临界势垒都随着过热度的增加而迅速变小,当过热度为0．9 K时,生成临界半径气泡的能量势垒约为0．1 K时的1．2％;当过热度为0．5 K时,能量涨落值基本与生成气化核心的临界势垒相当。In this article, the theory on the rapid depression process of supercritical CO2 fluid was investigated. The metastable characteristics of decompression CO2 in depression were analyzed and the nucleation mechanism in CO2 superheating liquid was explored. The calculation results of its thermodynamic model indicate that the radius and the potential barrier of critical bubble nucleus in the process are decreased rapidly with increasing of superheat degree. The potential barrier ratio is 1.2% when the critical bubble nucleus under the superheat degree of 0.9 K and 0.1 K. Energy fluctuation amplitude is approximately equal to the critical potential barrier when the superheat degree is 0.5 K.

关 键 词：临界CO2流体 迅速压降 亚稳态 成核机理 

分 类 号：TK121[动力工程及工程热物理—工程热物理]