THE INVESTIGATION OF THE EFFICIENCY OF PASSIVE COOLING BY PHASE-CHANGE MATERIALS IN LIGHT-WEIGHT BUILDINGS

摘要

Passive cooling with thermal storage in phase change materials (PCMs) is a very effective way to improve thermal stability of the rooms with light-weight envelope. The PCMs used as latent heat storage can absorb the building cooling load during the day and thus improve thermal comfort in a room or a building. But the efficiency of this kind of passive cooling significantly depends on the heat transfer rates between the ambient environment and the thermal storage material. The discharge of stored energy is commonly realised at night. But the temperature of outdoor air is often too high in summer for activation of the heat storage medium. Therefore, it is necessary to use a proper kind of ventilation at night. Two test rooms were built for comparative investigation of the efficiency of passive cooling with the use of the PCMs. One of the rooms has a common lightweight composition of the envelope; the second one has phase change materials incorporated in the building structures.