Abstract
In this study, a novel transient air dehumidifier that can meet the dehumidification demands at places without a constant energy supply and uses multi-stage desiccant plates was proposed. Based on the simulation methods, parametric and optimization studies were carried out to extend the effective working duration. First, the air handling processes, transient temperature and humidity distribution fields of a typical desiccant plate were investigated. The results indicated that there are three reasons for the generation of ineffective dehumidification sections. To reduce the proportion of the ineffective sections and to increase the effective working duration, parametric analyses were carried out on the desiccant plate, considering factors such as the initial water content (W-ini), inlet air humidity ratio (omega(a,in)), and length of the desiccant plate. The results show that, if the required outlet humidity ratio (omega*) is lower than 12-13 g/kg, W-ini = 0.1 kg/kg is preferred for omega(a,in) between 15 and 19 g/ kg. Subsequently, a dehumidifier with multi-stage desiccant plates (original dehumidifier) was designed, and the optimized stage number for different total thicknesses of desiccant plates was investigated to improve the dehumidification performance. When omega* is 10 g/kg, the recommended stage number is two. Finally, an advanced dehumidifier is introduced in which an ineffective desiccant plate can be replaced with a new desiccant plate. For the advanced dehumidifier, the proportion of ineffective sections can be effectively reduced by 14.6%-93.2%, and the effective working duration can be extended by 2.2%-34.8%, compared to the original dehumidifier that has the same total thickness as the desiccant plates.
NSTL
Elsevier