CO_2跨临界循环膨胀特性及机理

Characteristics and Mechanism of Expansion for Carbon Dioxide Transcritical Cycle

介绍了采用膨胀机的 CO2 跨临界循环的系统流程及典型工况 ,详细分析了膨胀中经历的亚稳态过程的成因和机理 ,指出气化的滞后对系统的危害 ,并对相变膨胀过程中的成核现象进行了热力学分析。在此基础上 ,结合 CO2 超临界膨胀过程的特点 ,阐明了气液相变介质中声速的确定方法 ,认为 CO2

This paper describes the flow chart and typical working condition of the CO 2 transcritical cycle with the expander. The cause and mechanism of metastable expansion process, the damage due to gasification delay and the nucleation in phase transition are analyzed. Based on those analysis, the speed of sound in the liquid\|vapor two phase fluid with phase transition is deduced with respect to the special characteristics of the CO 2 super\|critical expansion process. Finally,this paper also shows that it is feasible to use the quasistate theories of the traditional thermodynamics for the CO 2 super critical expansion process.