الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
Desiccant dehumidification systems are thermally regenerated systems that can be used either as standalone or as complementary additives for conventional cooling systems. One of their best competitive qualities is the potential to utilize low-grade heat sources for the regeneration process, thus decreasing electrical power consumption and scaling back the emissions of greenhouse gasses. In the present study, a novel multi-tray packed bed solid desiccant dehumidifier (MPBDD) was developed that can be used in conjunction with a traditional vapor-compression system. A lab-scale test rig was designed, fabricated, and tested under different operation conditions. The effect of the inlet humidity, temperature, and flow velocity on the system performance has been experimentally investigated. Further, two-dimensional (2D) model that considers the conservation of mass, momentum, and heat is built. A Linear Driving Force (LDF) model is used in the study to theoretically characterize the moisture adsorption properties of the solid desiccant (Silica gel). Also, the Saha, Boelman, and Kashiwagi equation has been applied to calculate the equilibrium water concentration. The model’s validity is evaluated by contrasting theoretical predictions with experimental findings. Additionally, by verifying a result of an article that has already been published. Experimental results show that the proposed configuration exhibited an adsorption capacity of about 27% higher than that of the conventional systems. Moreover, the pressure DROP through the newly designed desiccant bed was found to be 87% lower than that of the conventional wheel design. A dimensionless number called Total Performance Factor (TPF) was defined to be the ratio of heat dissipated for desiccant to pumping energy expended overcoming pressure DROP in the device. It was found that in certain experiments it attained an average value of around 250. To explore how the dehumidification system behaves under various operating situations and parameter variations, a parametric analysis was conducted. The system inlet velocity, relative humidity, temperature, and bed length are among the analyzed variables. It was discovered that the highest performance with the operating parameters of an input air mass flow rate to adsorbent mass ratio of 0.014 sec-1, inlet temperature of 32 oC, and relative humidity of 54% was achieved with bed length of 0.15m.