Experimental study of the thermal insulation performance of phase-change ventilated roofs

Abstract

In order to improve the thermal insulation effect of the PCM in the hot summer environment, this paper applies a combination of phase change energy storage technology, ventilation technology, and solar power generation technology. The zero energy operation of the device is realised while improving the roof insulation effect. In addition, three experimental models of the same size were constructed and the ventilation layer was innovatively designed. The experimental studies were carried out under two different conditions of outdoor environment measurement and indoor environment simulation for three consecutive days. The results show that the temperature of the inner surface of the roof and the indoor air temperature of Model 3 are lower than that of Model 2 under both experimental conditions, while the temperature of the inner surface of the roof and the indoor air temperature of Model 2 are lower than that of Model 1. In addition, the thermal performance of Model 3, such as the maximum reduction of the indoor temperature (MTR), the decay factor (DF), the time lag coefficient (TL), and the reduction of the heat flux (HFR), is also significantly better than that of Model 2. Moreover, the energy saving rate of Model 3 can reach 59.4%, which is 10% lower than that of Model 2. In conclusion, the new phase change ventilated roof proposed in this paper has better energy saving effect.