Developing a PCM-enhanced mortar for thermally active precast walls

This work presents an experimental research on the thermal properties of novel cementitious mortars incorporating microencapsulated Phase Change Materials intended to be used as the innermost layer in a precast radiant building component actively controlled by an integrated hydronic system. The characterization was developed in two steps: the first one focused on the effects of different fine aggregates and admixtures for a fixed PCM content and the second one on the effect of changing the amount of PCM. Results show that using silica aggregates and antifoaming admixture outperform the other options, producing mortars with statistically significant higher thermal conductivities, diffusivities and effusivities. Besides, increasing the amount of PCM significantly reduces conductivity and diffusivity, but the effusivity is practically invariant. This suggests that the mortar design has to be defined by predominantly focusing on diffusivity, in order to achieve appropriate heat penetration rates and activation times for an efficient system operation.INPHASE project (RTC-2015-3583-5) has been founded by the Ministry of Economy and Competitiveness within the National Programme for Research Aimed at the Challenges of Society, included in the framework of the Spanish National Plan for Scientific and Technical Research and Innovation 2013-2016, and has been co-financed by the European Regional Development Fund (ERDF), with the aim of promoting technological development, innovation and quality research