Abstract
We have developed a thermosensitive adsorbent that shows hydrophilicity below its phase transition temperature and hydrophobicity above one. For this reason, the adsorption amount of water vapor changes drastically around the phase transition temperature. Using this thermosensitive adsorbent, new desiccant air-conditioning system is proposed. This system is expected to save the energy to regenerate and to make the regeneration temperature low in comparison with the conventional systems. This system, however, requires the limitation condition to keep the temperature of the adsorbent below the phase transition temperature during adsorption.The aim of this work is to embody the concept of this new system with fin-tube type heat exchanger that is adopted as the adsorbent unit. Possibility of designing the reactor structure to overcome the limitation condition described above is examined. The surface of the fin and the tube is coated with the thermosensitive adsorbent. Water is employed as the coolant. For the simulation analysis, three dimensional finite element method is used. The calculated results show that it is possible to design the configuration of the heat exchanger to eliminate the heat of adsorption and simultaneously to keep the temperature of the adsorbent below the phase transition temperature. Furthermore, it is confirmed that this system requires much smaller amount of energy for its regeneration than the conventional systems and makes use of the low level waste heat sources below 333K.
