Article ID: 25-06AD
The objective of this report is to clarify the temperature and humidity distribution in the desiccant rotor in the variety of latent heat loads. Thus, we focused on the small sensors for “Internet of Things”. In the previous study, we created a measuring system to install the small sensing and logging unit inside the desiccant rotor, continuous measurement inside the rotating material was achieved. Firstly, we confirm the correcting method for sensor response delay when temperature and humidity input were changed was examined. And so, the basic experiment to confirm the response delay was conducted, the delay showed the same characteristics regardless of the differences in air temperature and humidity. The correction equations for the temperature and humidity were obtained. Secondly, an experiment was conducted to visualize the inside of the rotors. Two kinds of desiccant rotors with small sensors were created to compare the changes in dehumidification. The small sensors were embedded at five points from surface to another side of rotor. Fig. A-1 shows the absolute humidity distribution in the thickness direction of each desiccant rotor. In the case of xOA=14g/kgDA, Rotor A dehumidified by approximately 4 g/kgDA over three quarters of the thickness. However, dehumidification wasn’t occurred in the other one-quarter section. On the other hand, Roter C continued dehumidification throughout the entire thickness direction. Under the condition of xOA=5g/kgDA, Rotor C completed dehumidification within the first one-quarter section of the thickness direction. Fig. A-2 shows the variations of relative humidity and equilibrium adsorption amount in the rotor. From this figure, it can be observed that Rotor A does not perform dehumidification along the thickness direction, with the internal relative humidity decreasing from 23% to 8%. The equilibrium adsorption amount, obtained from the adsorption isotherm within Rotor A, is lower than 16 mg/g. The variation in dehumidification amount along the thickness direction is interpretable in terms of the characteristics of the adsorption isotherm. In the Case of the low latent heat load, Rotor A, which has a higher adsorption capacity, was lower amount of dehumidification than Rotor B. This is attributed to the difference in the slope of the adsorption isotherms in the low humidity range.
