Effects of building methods on thermal properties of phase change heat storage composite for solar greenhouse

Solar storage efficiency of solar greenhouse wall during the daytime is directly related to the construction of greenhouse wall layers and thermal properties of wall materials (thermal resistance, heat capacity, density etc.). Two composite phase change heat storage wallboards (mixed block and intercalation block) building by different methods were developed in this study. Mixed block was made by directly mixing the phase change materials (PCM) with cement mortar, and intercalation block was made by intercalating PCM into two cement mortar layers. The thermal properties under charge and discharge process, and the heat transfer performance of the two structures had been studied by the comparison experiment. The results showed that, under the same charge and discharge conditions, the mixed block completed heat storage/release in 70min, which was earlier than the intercalation block; the heat storage/release amount of mixed block was 10%/15% more than that of the intercalation block. A better thermal performance could be achieved by using the directly mixed way. The conclusion provides the reference for the scientific application of phase change thermal storage technology in solar greenhouse.