Comparative analysis of energy discharge characteristics between hollow fiber membrane and flat membrane energy accumulators. (November 2021)

• Record Type: Journal Article
• Authors: Sun, Surui; Sun, Honglei; Song, Qinglu; Wang, Dechang; Kong, Xiangqian; Li, Yanhui
• Is Part Of: International journal of refrigeration. Volume 131(2021)
• Page Start: 874
• Page End: 886
• Publication Date: 2021-11
• Subjects: Membrane energy accumulator -- Simulation -- Heat and mass transfer -- Hollow fiber membrane -- Flat membrane; Accumulateur d'énergie à membrane -- Simulation -- Transfert de chaleur et de masse -- Membrane en fibre creuse -- Membrane plate; Refrigeration and refrigerating machinery -- Periodicals; 621.56
• DOI: 10.1016/j.ijrefrig.2021.07.042
• Languages: English
• ISSNs: 0140-7007

Abstract

Highlights: Hollow fiber and flat membrane energy accumulators are designed and simulated. Dynamic mathematic models of heat and mass transfer in full-scale MEAs were built. Influence of membrane to membrane and the boundary of the MEAs were considered The reliability of mathematic models has been verified by the experimental results. Triangular arrangement of the fibers is more conducive to the mass transfer process. Abstract: The hollow fiber membrane energy accumulator (HFMEA) and the flat membrane energy accumulator (FMEA) were designed. Dynamic mathematic models of the heat and mass transfer in the full-scale membrane energy accumulators (MEAs) were built in order to consider the membrane-to-membrane interactions and boundary effect in MEAs. The reliability of mathematic models has been verified by the experimental results. The maximum relative deviations of the mass transfer flux and solution temperature were 14.9 % and 14.6 %, respectively. The change rate of LiBr mass fraction in the FMEA was 1.38 times of that in the HFMEA. The hollow fiber membrane bundle in HFMEA is more conducive to the mass transfer process when the arrangement of the fibers is triangular. When the length of the membrane channel increased from 50 mm to 160 mm in HFMEA, the mass transfer per membrane surface area decreased by about 5 %. With increasing the vapor inlet pressure from 700 Pa to 1500 Pa, the mass transfer flux was tripled. And the average temperature of the solution increased by more than 3.75°C in 10 minutes. If the membrane filled density increased from 1.4 % to 2.1 %, the mass transfer flux increased to 2.04 times in FMEA.