Performance of counter flow membrane-based annular pipe liquid desiccant air conditioner

Abstract

The present study comprises an experimental and numerical simulation of a counter flow membrane-based annular pipe liquid desiccant air conditioner (AP_LDAC) system. The experimental rig was constructed by using DuPont™ Tyvek® Solid as semi-permeable membrane and it has simplier structure compared to other types of membrane-based dehumidifiers. To validate the numerical data, experiments were carried out at different air side Reynolds (Re) number. The 3D numerical simulation of counter flows of the AP_LDAC system presented good agreement (R-square: 0.9659) with experimental data, as a result of the validation. Once the reliability of numerical data were verified, the mass transfer coefficient of counterflow obtained by designed system was revealed and optimized numerically by investigating for various aspect ratios, Reynolds (Re) and Schmidt (Sc) numbers. The derived Sh model was predicted over COMSOL Sh numbers with error interval from 0.1% to 10%. The effect of air inlet temperatures on temperature, concentration distributions and efficiency of the optimized AP_LDAC system were also investigated. The dehumidification efficiency was found as 99% for the maximum aspect ratio and the lowest Re number.