Thermal behavior evaluation of a radiant floor heating system incorporates a microencapsulated phase change material

Abstract

The rapid growth of urbanization and the increase of internal comfort requirements impact negatively the environment and the energy consumption of the building sector. Therefore, it becomes very crucial to provide an internal thermal comfort with environmentally friendly techniques. In cold regions, the heated floor incorporates a phase change material is an outstanding technique that can ensure high thermal performance and meet the thermal comfort requirements of occupants. In the present study, the thermal performance of a heated floor impregnates a microencapsulated PCM was numerically studied and evaluated. The heated floor system consists of tubes where hot water circulates, buried under the ground made up of different layers. The thermal waves rise from below heat up the ground which in turn transmit the flow recovered. The integration of a PCM in the floor mainly aims to benefit from its considerable storage ability in order to reduce the energy consumption of the heating system and stabilizes internal temperature around the set temperature of comfort in a long time. To evaluate the PCM under-floor heating system a physical model based on two-dimensional computation is used. The calculations are made by considering the enthalpy approach and applying the numerical finite volume method. The effect of different parameters such as microcapsules integration, mass fraction, tubes inter-distance and PCM type on the heated floor thermal performance are evaluated and discussed. The obtained results show that the best performance of the heated floor is got when 15% of microcapsules are placed above the heating tubes. Consequently, an increase of 4 °C in the amplitude and a phase shift of 5 h 30 min compared to the base case (heated floor without PCM) are obtained.