Influence of the velocity ratio and rotational speed on the polymer based desiccant dehumidifier

Nowadays, it’s essential to reduce our reliance on conventional air conditioning units and switch to desiccant-based dehumidifiers and air conditioners. This shift promotes sustainability, protects the environment from harmful gas emissions, and minimizes energy consumption. The current work centres on developing a polymer-based dynamic desiccant dehumidifier system. This involves studying the velocity ratios between the dehumidifier and regenerator air at various rotational speeds. Four sets of velocity ratios and four sets of rotational speeds are included in the matrix preparation. The results indicated that the system performed optimally with a velocity ratio range of 1.00 to 0.20, demonstrating improved temperature and humidity changes as well as dehumidification efficiency. In contrast, the highest velocity ratio range of 4.00 to 0.80 achieved the maximum rate of moisture removal, performance coefficient, and coefficient of mass transfer at an optimum rotational speed of 24.0 rpm. Beyond these ranges, performance declined significantly. This unit reached a maximum rate of moisture removal of 0.23 g/s, dehumidification efficiency of 83.7%, a coefficient of performance of 5.36, and a coefficient of mass transfer of 6.67 kg/m²-s. Highlights As the velocity ratio decreases, both efficiency & moisture removal rate increase. Dehumidification performance improves up to 24.0 rpm, and then it declines. COP values of 1.87, 3.25, 4.24, and 5.36 are achieved for VR of 1.00, 2.00, 3.00, and 4.00. Power consumption & pressure drop rise with the velocity ratio & wheel speed. Mass transfer coefficient of 6.67 kg/m²·s is obtained at 24.0 rpm & VR of 0.80.