A ventilated cooling ceiling with integrated latent heat storage: test room measurements

Aventilated cooling ceiling with phase change material (PCM) was installed and measured in a 20 m2 test room. The PCM used was DELTAw-COOL 24, a salt hydrate from the company Do "rken with a melting range of 22-288C. The PCM was encapsulated in polycarbonate containers which were laid on top of the bearing for the plaster boards. The amount of PCM installed was 9 kg/m(2). The ceiling was rear ventilated to improve heat transfer between the PCM and the room air. During the cooling mode, the ventilation was purely in circulating operation with a volume flow rate of 97 m3/h (air exchange rate of 2/h). To regenerate the PCM, cooled air was inserted into the ceiling with a volume flow rate of 140 m(3)/h (air exchange rate of 3/h). Different positions for the containers were tested. The PCM in the ceiling delayed the rise in the room air temperature significantly. The PCM stayed active for 12-16 h, depending on the position of the containers. While the cooling power of the air flow alone was very small (30-40 W for the 20 m(2) test room), a significant amount of heat was transferred directly through the plaster boards of the ceiling.