Temperature–heat diagram analysis method for heat recovery physical adsorption refrigeration cycle – Taking multi-stage cycle as an example

• Published in: International journal of refrigeration Vol. 74; pp. 254 - 268
• Main Authors: Xu, S.Z., Wang, R.Z., Wang, L.W.
• Format: Journal Article
• Language: English
• Published: Paris Elsevier Ltd 01.02.2017; Elsevier Science Ltd
• Subjects: Adsorption; Adsorption refrigeration; Cycle multiétagé; Diagramme T-Q; Dissipation d’entransie; Entransy dissipation; Entropy; Exergy; Froid à adsorption; Heat exchange; Heat exchangers; Heat recovery; Heat transfer; Multi-stage cycle; Optimization; Refrigeration; Récupération de chaleur; T–Q diagram; Multi-stage cycle; Diagramme T-Q; T–Q diagram; Froid à adsorption; Cycle multiétagé; Adsorption refrigeration; Entransy dissipation; Récupération de chaleur; Heat recovery; Dissipation d’entransie
• ISSN: 0140-7007; 1879-2081
• DOI: 10.1016/j.ijrefrig.2016.09.021

•The method of temperature–heat (T–Q) diagram analysis was proposed.•Area along T axis represents the irreversibility degree in heat transfer process.•Multi-stage heat recovery physical adsorption refrigeration cycles were analyzed.•Heat exchange configuration or heat exchanger network can be optimized.•T–Q diagram optimization is actually intuitional entropy production minimization. The method of temperature–heat (T–Q) diagram analysis was proposed in this article. In T–Q diagram, the area between two process curves along the temperature axis represents the irreversibility degree of heat transfer, which has the same dimension with entransy dissipation. T–Q diagram can be used to optimize the heat exchange configuration and the heat exchanger network of adsorption refrigeration systems. The proposed T–Q diagram and traditional energy, exergy and entropy analyses were adopted to a multi-stage heat recovery adsorption refrigeration system. Results show that the optimal heat recovery schemes determined through T–Q diagram and cycle entropy production analyses are identical, while T–Q diagram is more intuitional since the analysis procedure is done graphically. T–Q diagram can also be applied to analyze experiment related results of process temperatures, and is capable of giving an estimation of the performance improvement for heat recovery cycle.