摘要
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 ,指出了气化滞后对系统的危害 ,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 超临界膨胀过程可近似按照经典热力学的准静态理论进行分析 。
The flow process and thermaodynamic characteristics for CO 2 transcritical cycle with expander at the typical working case was described. The cause and mechanism of metastable expansion process was presented, the damage due to gasification delay was pointed out, and nucleation in phase transition was analysed. The velocity of sound in the liquid vapor two phase fluid was determined, moreover the reasons of using quasistate theories was also illustrated.
出处
《流体机械》
CSCD
2002年第6期40-43,36,共5页
Fluid Machinery
基金
国家自然科学基金项目(59876028)
天津大学"211工程"重点学科建设项目(TD211950106)
关键词
CO2跨临界循环
膨胀过程
亚稳态
相变
制冷
CO 2 transcritical cycle
expansion
metastable state
phase transition
