摘要
超临界二氧化碳循环传统㶲分析存在不能提供有关㶲损失全面信息的缺点,该文采用高级㶲分析方法揭示双回路超临界二氧化碳再热再压缩循环每个系统组件的内源、外源、可避免、不可避免、内源可避免、内源不可避免、外源可避免和外源不可避免㶲损失.结果表明:在真实、理想和不可避免工况下,系统的热效率分别为48.61％、58.81％和55.07％;总㶲效率分别为67.60％、83.76％和77.95％.系统总的可避免㶲损失为27.37MW,约占总㶲损失的47％.在可避免㶲损失中,38.62％是内源性的,61.38％是外源性的.在提升系统整体性能方面,传统㶲分析获得的组件性能提升优先顺序与高级㶲分析并不相同.前者建议优先顺序为预冷器、高温回热器、预热器和再热器,而后者建议优先顺序为预冷器、主压缩机、再压缩机和低温回热器.尽管高温回热器、预热器和再热器的㶲损失较大,但其自身改进潜力较小.
Abstract
The traditional exergy analysis of the supercritical carbon dioxide(S-CO2)cycle is limited in providing comprehensive information on exergy destruction.In this paper,the advanced exergy analysis method is adopted to reveal the endogenous,exogenous,avoidable,unavoidable,avoidable endogenous,unavoidable endogenous,avoidable exogenous,and unavoidable exogenous exergy destruction for each system component of the dual-circulation recompression S-CO2 cycle with reheating.The study reveals that the overall thermal efficiencies of the system are 48.61％,58.81％and 55.07％under real,ideal and unavoidable conditions,respectively;the overall exergy efficiencies are 67.60％,83.76％and 77.95％,respectively.The value of the overall avoidable exergy destruction for the whole system is 27.37 MW,accounting for 47％of the total exergy destruction.Among the avoidable exergy destruction,38.62％of it is endogenous while the percentage of exogenous is 61.38％.The priority order of component performance improvement based on traditional exergy analysis is different from that obtained by advanced exergy analysis.The former recommendation proposes an order of PC,HTR,PH,and RH,while the latter suggests a different priority sequence:PC,MC,RC,and LTR.The exergy destructions of HTR,PH and RH are relatively large,but their improvement potential is minimal.
基金项目
中央高校基本科研业务费专项资金项目(3072020CFT0307)
国家科技期刊平台
NSTL
万方数据