CFD simulation and exergy evaluation of geometrical characteristics effects of refrigeration tubes in a 3-fluid LAMEE

Zabihi, Aydin; Pourmahmoud, Nader

doi:10.22061/jcarme.2024.10051.2341

Document Type : Research Paper

Authors

Mechanical Engineering Department, Urmia University, Urmia, Iran

https://doi.org/10.22061/jcarme.2024.10051.2341

Abstract

Cooling tubes are inserted into the desiccant dehumidifier liquid of a 3-fluid liquid-to-air membrane energy exchanger (LAMEE) to regulate the temperature of the dehumidifier liquid. As a result, the 3-fluid LAMEE's performance is significantly influenced by the refrigerated tubes. The numerical analysis of the present work shows that the number of chilled tubes and their inner diameter affect the effectiveness (total, latent, and sensible) rate of moisture removal, adequate cooling power, and exergy loss. Additionally, the dehumidifier liquid channel receives the addition of wavy cooling tubes for the first time. The relationship between wave height and wave length is known as wave steepness and its impact on efficiency and energy loss is also examined. Numerical studies show that the number and inner diameter of the cooling tubes have a direct correlation with the efficiency of the 3-fluid LAMEE. The improved the efficiency, the more cooled tubes there are and the larger their diameter. Furthermore, both exergy loss and without dimensions exergy loss increase with the quantity and diameter of refrigerated tubes. The sensible and latent effectiveness of the 3-fluid LAMEE is increased by the wavy refrigeration tubes as compared to straight tubes; the augmentation of the sensible and latent effectiveness increases with wave steepness.

Graphical Abstract

Keywords

Main Subjects

Computational Fluid Dynamics (CFD)

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