Experimental and Numerical Investigation of Composite Phase Change Materials for Building Energy Saving

Composites composed of paraffin wax and copper foam with porosity of 95 % and pore density of 15 ppi, 30 ppi and 50 ppi were prepared by the melt impregnation method. Two building models with the same dimension were fabricated, one had a phase change composite board of 50 ppi copper foam/ paraffin on the roof of the building model, and the reference model applied a thermal insulation foam board on the roof of the model for comparison. The heat transfer experiment was conducted with a constant heat flux. EnergyPlus software was also employed to simulate the energy saving effects of the building models. Experimental results showed that the phase change composite board delayed the highest indoor temperature for 1.5 h, and it also reduced the indoor maximum temperature by 1.2 degree and the indoor energy consumption by 21 %. The simulation results showed that the phase change composites board delayed the appearance of the highest indoor temperature by 1.3 h and reduced the highest indoor temperature by 1.1 ℃, and the maximum indoor energy consumption decreased by 19 %. The copper foam/paraffin composite material can effectively improve the thermal comfort and reduce the energy consumption of the building model.