Abstract
An optimum operating and design concept for miniaturization of adsorbent desiccant wheel were presented by means of numerical analysis of simultaneous heat and mass transport in the desiccant wheel. First, the influence of the operating parameters, such as regeneration air temperature and air flow rate, and design parameters, such as the ratio of the adsorption area and length of the wheel, on the optimum rotation speed and amount of dehumidified water were investigated. Based on these results, the minimum volumes of the desiccant wheel achieving the certain dehumidification performance were calculated under various air conditions. As an example of the results, the minimum volume of the desiccant wheel, 0.019 m3, which was 30 % smaller than that of the conventional one, was obtained to achieve 8 g/kg of the amount of dehumidified water when regeneration air was 80 oC, 11.2 g/kg, and adsorption air was 35 oC, 20 g/kg. In order to satisfy this volume, the retention time, which could be calculated dividing the rotor length by air velocity, was calculated as 0.075 s, and ratio of the adsorption area was calculated as 0.55. Consequently, this study could conduct an optimum operating/design concept for the miniaturization of the desiccant wheel although the above mentioned reduction in volume, 30 %, is possible to range from 5 to 50 % due to the accuracy of the estimation.
