Initial Development of a Combined PCM and TABS Solution for Heat Storage and Cooling

This paper investigates heat storage and cooling concept that utilizes both phase change material (PCM) and a thermal active building system (TABS) implemented in a hollow core concrete deck element. PCMs are promising materials for improving the heat storage capacity of a building due to their significant thermal energy storage capabilities. The TABS has a potential for increasing the exploitation of the thermal mass of the building, which is rarely exposed for heat transfer.The main objective of this study is to optimize the location and amount of PCM in a hollow core deck in order to optimize heat storage capacity. A series of simulations were conducted using the COMSOL program to obtain knowledge regarding the dynamic heat storage capacity of the investigated hollow core deck element as a function of the amount and location of PCM. Furthermore, the dynamic heat storage capacity of a passive deck element and the possible cooling power of the thermally activated deck element were predicted and then compared. Finally, results obtained from precise numerical simulations in COMSOL Multiphysics were compared with results calculated in the whole building
simulation software BSim. Initial results indicate that the best location of the PCM in the hollow core concrete deck element is close to the surface that is facing to the room. Moreover, the heat transfer coefficient on the surface of the deck has a very significant impact on the heat storage capacity of the concrete deck element.