中低品位热源有机朗肯循环系统的热力学分析

Thermodynamic Analysis of Organic Rankine Cycle System for Medium and Low Grade Heat Sources

基于热力学第一定律和第二定律,分析了以R113作为循环工质,需回收的废热为52.624kW的有机朗肯循环(ORC)发电系统在变工况下的热力性能,其中,热力性能由系统热效率和火用效率作为评价标准。结果表明,当蒸发压力不变时,蒸发器出口温度对ORC系统的热效率及火用效率影响很小;蒸发压力或膨胀比增大时,ORC系统的热力性能也随之提高,影响较显著。这些将为ORC系统的性能优化提供理论基础。

Based on the first law of thermodynamics and the second law,the thermal performance of the organic Rankine cycle(ORC)power generation system with R113 as the circulating working fluid and the waste heat of 52.624kW to be recovered under variable working conditions is analyzed.Performance is evaluated by system thermal efficiency and exergy efficiency.The results show that when the evaporation pressure is constant,the evaporator outlet temperature has little effect on the thermal efficiency and the fire efficiency of the ORC system.When the evaporation pressure or expansion ratio increases,the thermal performance of the ORC system also increases,and the effect is more significant.These will provide a theoretical basis for the performance optimization of the ORC system.