有泵/无泵ORC系统的单压/双压发电性能分析

Analysis of Power Generation Performance of ORC System With/Without Pump in Single/Dual Pressure Mode

随着社会的快速发展,能源问题日益凸显,有机朗肯循环(Organic Rankine Cycle,ORC)是一种回收低品位废热、节约能源的有效手段。本文建立了有泵/无泵、单压/双压对应的4种ORC系统,并针对4种系统进行了发电性能分析,对比了4种系统在不同工况下的发电量和[火用]效率。首先在设计工况下,以发电量为优化目标得到了最优蒸发温度和最优工质流量。然后在最优设计参数下,研究了当实际运行偏离设计工况时,即热源温度波动时以及在不同季节4种系统的性能变化规律。结果表明,双压无泵系统发电性能最好,同时结构和控制也最复杂。

With the rapid development of society,energy issues are becoming increasingly prominent.The organic Rankine cycle(ORC)is an effective means of recovering low-grade waste heat and saving energy.In this paper,four ORC systems,i.e.,with/without pump and single/dual pressure,are established.The analysis of power generation performance was carried out for the four systems.Specifically,the power generation and exergy efficiency of these systems under different working conditions were compared.First,under the design conditions,the optimal evaporation temperature and the optimal flow rate of working fluid were obtained with the power generation as the optimization goal.Then with the optimal design parameters,the off-design performance of the four systems was investigated when operating with fluctuating heat source temperature and in different seasons.The simulation results showed that the dual-pressure pumpless system has the greatest power generation performance but the most complicated structure and control strategy.