一种基于正逆循环耦合的低温制冷系统

A New Refrigeration System for Low-Temperature Applications Based on the Power/Refrigeration Cycle Coupling

以能的梯级利用原理为指导原则,基于正逆循环耦合方法,本文提出了一种利用中温显热热源制取较低温度冷量的复合式制冷系统,该系统由动力子循环、吸收式制冷子循环与压缩式制冷子循环有机耦合而成。通过模拟计算,对系统热力性能进行了评估,系统制冷性能系数(COP)达到了0.277,与常规余热双级吸收式制冷系统相比,提高了50%左右。通过(火用)平衡和t-Q图分析,发现热源利用过程不可逆损失大幅降低是系统性能提升的主要原因。本文还研究了热源烟气温度T_H和冷却水温度T_(CW)对系统性能的影响,为指导系统设计提供了依据。

Under the guidance of the principle of energy cascade utilization,this paper proposed a new refrigeration system for low-temperature applications by using mid-temperature sensible heat.Based on the coupling of power and refrigeration cycles,the proposed system comprises a power generation subcycle,an absorption refrigeration subcycle,and a compression refrigeration subcycle.Simulation calculation was conducted,and system＇s thermodynamic performance was evaluated.The results show that the system＇s coefficient of performance（COP） reaches 0.277,which is 50%higher than that of the traditional two-stage absorption refrigeration system.The energy saving mechanism was elucidated by exergy analysis and was displayed by t-Q diagrams.The dramatic decrease of exergy destruction in the utilization process of heat source was the main contributor for performance improvement.Moreover,this paper studied the effects of heat source temperature TH and cooling water temperature T（CW） on the system＇s performance,providing the guidance for system design.