Simulation CFD de la performance d'un déshumidificateur à déshydratant liquide avec des plaques lisses et rugueuses

Translated title of the contribution: CFD simulation of liquid desiccant dehumidifier performance with smooth and rough plates

Hao Lu, Lin Lu

Research output: Journal article publicationJournal articleAcademic researchpeer-review

2 Citations (Scopus)

Abstract

Liquid film pattern is crucial for mass transfer performance of falling film liquid desiccant dehumidifier (LDD). Rough plate may be effective on modifying the liquid film pattern and then enhance dehumidification efficiency of the LDD. Therefore, this study aims to investigate unsteady gas-liquid flow and dehumidification performance of falling film LDD for smooth and rough plates. The gas-liquid flow was predicted by the RNG k-ε turbulence model while the interface patterns were tracked by volume of fluid (VOF) model. The dehumidification performance was simulated by user-defined function (UDF) codes based on the penetration theory. The dynamic liquid film characteristics, the gas-liquid flow fields, the mass fraction fields and dehumidification enhancement mechanisms were analyzed and discussed. Moreover, the effects of inlet air velocity and inlet desiccant concentration on the mass transfer characteristics were investigated. The results showed that the ribbed plate can induce liquid film waves and significantly enhance dehumidification performance of the falling film LDD. The dehumidification enhancement can reach 30.9% by the rough plate when inlet air velocity is 0.5 m s−1 and inlet desiccant concentration is 30%, compared with the smooth plate case. The enhancement mechanisms of dehumidification by the rough plate include the liquid film waves, the flow vortex and high-value TKE near the gas-liquid interface. The outlet mass fraction of water vapor is decreased when the inlet air velocity is lower and the inlet desiccant concentration is higher. The rough plate is effective for the mass transfer enhancement for different inlet air velocity and desiccant concentration.

Translated title of the contributionCFD simulation of liquid desiccant dehumidifier performance with smooth and rough plates
Original languageFrench
Pages (from-to)1-12
Number of pages12
JournalInternational Journal of Refrigeration
Volume124
DOIs
Publication statusPublished - Apr 2021

Keywords

  • Heat and mass transfer
  • Liquid desiccant dehumidifier
  • Numerical simulation
  • Rough plate

ASJC Scopus subject areas

  • Building and Construction
  • Mechanical Engineering

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