摘要
随着能源问题日益突出,低温烟气余热深度利用成为了研究热点领域。其中,有机朗肯循环是实现低品位余热转换为电能的一有效途径。基于热力学基本定律,以有机朗肯循环系统最大做功能力和效率为目标函数,计算分析了10种不同工质在亚临界状态下以上两种目标函数的特性。结果表明,每种工质均存在一最佳蒸发温度使循环净输出功最大,而且工质临界温度越高,对应的最佳蒸发温度也越高;热源温度相同时,系统效率随窄点温差增大而减小;同一窄点温差时,当热源温度不超过临界温度两倍的窄点温差时,效率有一最大值;反之,则随蒸发温度升高不断增大。这些将为有机朗肯循环工质选择和性能优化提供理论指导。
Since energy issues become increasingly on the utilization of low-grade waste heat. Organic transform the low-grade waste heat to electricity. urgent in the world, considerable Rankine cycle （ORC） is one of th In this study, the maximum user interest has focused e effective ul output routes to work and exergy efficiency of the ORC are selected as the objective functions. 10 different working fluids are chosen to comprehensively investigate and analyze the important characteristics of the two objective functions in the subcritical state. The results show that an optimal evaporating temperature exists for each working fluid, at which the useful work is the maximum. Moreover, the higher the critical temperature, the higher the optimal evaporating temperature. It is found that for the same heat source, the exergy efficiency decreases with the increase of the pinch point temperature difference. For the same pinch point temperature difference, the exergy efficiency has a maximum value when the heat source inlet temperature is twice of the pinch point temperature difference lower than the critical temperature. Otherwise, the exergy efficiency keeps increasing with the heat source temperature. These results provide some valuable guidance to optimize the ORC system and screen working fluid.
出处
《化工学报》
EI
CAS
CSCD
北大核心
2013年第3期820-826,共7页
CIESC Journal
基金
国家重点基础研究发展计划项目(2011CB710701)
关键词
有机朗肯循环
最佳蒸发温度
[火用]分析
最大做功能力
organic Rankine cycle
optimal evaporating temperature
exergy analysis
maximum useful work
