Abstract
Phase Change Materials (PCMs) are just as effective at reducing the energy exchange of a building with its surroundings as thermal insulation. Nanoparticles (NPs), on the other hand, can alter the thermal response of PCMs by altering their thermal properties. In this study, with emphasis on building heat balance, the thermal performance of CaCl2 center dot 6H(2)O as PCM and CaCl2 center dot 6H(2)O/CsxWO3 as nano PCM were compared. The building heat balance was analyzed annually in nu-merical analysis. CsxWO3 nanoparticles were added to CaCl2 center dot 6H(2)O at 0.25, 0.5, 0.75 and 1 wt%. The thermal conductivity and enthalpy of phase change of CaCl2 center dot 6H(2)O both underwent a decreasing trend so that at 1 wt%, the former and latter parameters were decreased by 30.5 and 24.2%, respectively. The performance of the building was first analyzed with CaCl2 center dot 6H(2)O and it was found that it reduces the building heat balance by 8.2%. Heat balance was evaluated for CaCl2 center dot 6H(2)O/CsxWO3 and it was found that CsxWO3 have acceptable thermal behavior only at 0.5 wt%. In this mass fraction, the heat balance decreases by 1%, and at 0.25, 0.75, and 1 wt%, it increases by 0.13%, 0.52% and 4.6%, respectively. The most important result was that it is necessary to perform annual calculations to compare the performance of nano-PCM and PCM considering the energy analysis of the building.