Energy and exergy performance investigation of transcritical CO_2-based Rankine cycle powered by solar energy  

作　　者：ZHANG XinRong LI XiaoJuan 

机构地区：[1]Department of Energy and Resources Engineering, College of Engineering, Peking University, Beijing 100871, China [2]Energy Conversion Research Center, Department of Mechanical Engineering, Doshisha University, Kyoto 630-0321, Japan

出　　处：《Science China(Technological Sciences)》2012年第5期1427-1436,共10页中国科学（技术科学英文版）

基　　金：supported by the National Natural Science Foundation of China (Grant No.50976002)

摘　　要：A comprehensive performance evaluation of a solar assisted transcritical CO2-based Rankine cycle system is made with exergy analysis method. The actual thermal data taken from the all-day experiment of the system are utilized to determine energy transfer and the exergy destructions in each component of the system. In addition, a hypothetical carbon dioxide expansion turbine is introduced, then two thermodynamic models for solar transcritical carbon dioxide Rankine cycles with a throttling valve (experiment) and with an expansion turbine have been established with exergy analysis method. The obtained results clearly show that solar collector contributes the largest share to system irreversibility and entropy generation in the all-day working state, and the exergy improvement potential of solar collector is the maximum in the working state. So this component should be the optimization design focus to improve system exergy effectiveness. For the cycle with the turbine, the energy efficiency and the entropy generation are not much higher than the cycle with throttling valve, but the exergy efficiency of the cycle with turbine is twice of the cycle with throttling valve. It provides more guidance when the transcritical CO2-based Rankine system is in a large-scale solar application.

关 键 词：transcritical C02 rankine cycle solar energy exergy analysis exergy improvement potential 

分 类 号：TK513[动力工程及工程热物理—热能工程] TS106.4[轻工技术与工程—纺织工程]