Evaluation of a Three-Sector Desiccant Wheel for Integrated Cooling, Heating, and Dehumidification in Buildings

Abstract This study investigates the performance of a desiccant wheel configured into two process sections (P1 and P2) and a regeneration section (R), designed to meet the simultaneous demands of humidity control, cooling, and heating in industrial and building environments. The wheel's performance was assessed based on the exit humidity ratio and temperature under three conditions: precooling of P1 streams, precooling of P2 streams, and no precooling, using a two-dimensional mathematical model. Without precooling, P2 demonstrated superior dehumidification, making it ideal for low-humidity industrial processes, while P1 is better suited for moderate-humidity applications, such as air conditioning systems in buildings. To evaluate the impact of sensible precooling, a precooler was first placed before P1, but this setup compromised P2's dehumidification, and P1 failed to meet heating, ventilation, and air conditioning (HVAC) standards. Relocating the precooler to P2 yielded better results, with P2 delivering low-humidity air for industrial applications, while P1 provided air with moderate humidity to meet the humidity control requirements of air conditioning, and after post-cooling, air from P1 can achieve temperatures appropriate for air conditioning. The regeneration section (R) produced warm, humid air, which can be useful for heating industrial or building spaces in winter. This configuration offers a flexible solution for humidity control in industrial environments and energy-efficient HVAC systems for building applications.