Thickness Determination of a Three-layer Wall with Phase Change Materials in a Chinese Solar Greenhouse

Chinese solar greenhouse (CSG) is an energy saving production building that used to grow vegetables in winter. The north wall of CSG plays an important role concerning the vegetable production without additional heating during the winter months. This paper studies a north wall of a CSG which is built with three layers, the phase-change material wallboard/the block brick /the insulation board. To determine the optimum thickness of the three-layer wall for passive solar heating, a solar greenhouse model is constructed by Energy Plus v8.6 to study the dynamic heat storage/release characteristics of the wall and develop methods to estimate its thickness. The results show that the optimum thicknesses of the phase-change material wallboard, the block brick and the insulation board of the expanded polystyrene in Beijing are about 50 mm, 620 mm and 60 mm, respectively. The results can provide reference for the optimization design and thermal performance analysis of solar greenhouse.