Thermal Performance of a Floor Heating and Cooling System with Air Heat Source by CFD Simulation

The authors have developed a hybrid floor heating system with radiant panels heated by air from an air-conditioner by experiments using a full scale model room to examine the feasibility of the system and the psychological response of people. However the original system was rather large to be applied to the actual space. The object of this study was to investigate the thermal performance of the improved system with new radiant panels designed for the practical use to minimize the thickness of the panels and to change the airflow path inside the panels by experiments and CFD simulation. In this paper, CFD simulation was performed to investigate airflow inside the panel and the distribution of floor surface temperature for the different configuration of radiant panel, supply air temperature and heating load of the room. As a result, the floor surface temperature was kept high by improving thermal insulation on the wall. The amount of supply air sent to the space of the panel was increased by narrowing the panel flow path. In addition, it was verified that the distribution of the air was significantly affected by the convex part between the center and the side path. The uniform air distribution inside the panel and surface temperature on the floor were obtained by the improved radiant panel.