Numerical Study of Heat Gradient and Crossing Energy to around Building Walls Including Phase Change Materials in Kashan Temperature Conditions

Authors

Abstract

Because of the high capacity of Phase Change Materials (PCM), the application of these materials in the variant parts of buildings leads to an improvement in temperature conditions as well as a reduction in energy consumption. Due to the high dependency of the performance of these materials on ambient temperature fluctuations, their application in climates with extreme temperature fluctuations has significant impacts on reducing the temperature fluctuations inside buildings as well as the consumption of energy. In this study, the high temperature of Kashan, as ambient temperature, and the walls of normal concrete with the thickness of 10 and 20 cm and the height of 100 cm were modeled in FLUENT software. Some kinds of PCM for these temperature conditions were considered, and the best was chosen. Numerical results show that the presence of PCM has reduced the temperature fluctuations of the inner surface of the walls about 4 ° C, and the position in the inner surface has better result. However, totally the changing in PCM position has not had great impacts on the ultimate results. Moreover, a change in the number of PCM thickness does not have a great influence on the temperature function. Based on the results, it can be concluded that parafin has a better function for Kashan’s climate and that every climate requires an appropriate PCM.

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