Differences of energy saving quantities for absorption‐compression hybrid cooling systems with cascade condenser and cascade subcooler. (13th July 2021)

• Record Type: Journal Article
• Authors: Peng, Zeyu; Li, Zeyu; Zeng, Junquan; Xu, Yongrui
• Is Part Of: International journal of energy research. Volume 45:Number 13(2021)
• Page Start: 19439
• Page End: 19452
• Publication Date: 2021-07-13
• Subjects: absorption‐compression -- cascade condenser -- cascade subcooler -- energy saving -- process decoupling -- refrigeration; Power resources -- Periodicals; Power (Mechanics) -- Periodicals; Power resources -- Research -- Periodicals; 621.042
• DOI: 10.1002/er.7033
• Languages: English
• ISSNs: 0363-907X

Abstract

Summary: Absorption‐compression hybrid cooling systems with cascade condenser and cascade subcooler are able to effectively reduce compressor power by low‐grade heat. However, differences of both energy saving quantities still cannot be explained exactly through various types of coefficient of performance ( COP ) indicators, which is adverse for the decision‐making of appropriate layouts. In this regard, we attempt to illustrate the above‐mentioned issue from the new standpoint, that is, by decoupling processes and considering the limitation of thermodynamic cycles and refrigerant characteristics. It is found that there is the critical heat quantity corresponding to the order transition of energy saving for both layouts at first. Subsequently, critical heat quantities for different working conditions are obtained and analyzed. Moreover, expressions regarding critical heat quantities for five refrigerants are fitted by the neural network. It is displayed that the average difference between the critical heat quantity for R1234yf, R1234ze(E), R290 and R32 and that for ammonia is 7.89%, 4.08%, 4.78%, and 4%, respectively. The paper is helpful for decision‐making of absorption‐compression hybrid cooling systems with cascade condenser and cascade subcooler to enhance the amount of energy saving for certain quantities of low‐grade heat. Abstract : Differences of energy saving quantities for both layouts are obtained exactly There is a critical heat quantity corresponding to order change of energy saving Layouts with cascade subcoolers saves more energy as heat quantity is less Critical heat quantities for different conditions and refrigerants are obtained