A Study of the Application of Phase Change Energy Storage Material to Building Materials

This study adds the concept of a heat rejection layer to building materials, discusses the influence of different cement brick structures, configurations, and quantities of heat rejection layers on the upper and lower surface temperature rises of bricks, and seeks the optimized cement brick for reducing the day-night temperature difference, in order to reduce indoor temperature, enhance human comfort, and reduce air conditioning consumption to implement energy saving and carbon reduction. The experimental results show that the PCM interlayer in the cement brick can slow the temperature rise of the lower surface of bricks. When the simulated sunlight is stopped, the PCM interlayer plays the role of heat storage in the brick, so that the brick preserves heat, slowing the temperature drop of the lower surface. The sandwich design of one layer of EPS between two pieces of PCM can reduce the heat transfer rate between two PCMs, thus, the PCM material near the lower surface of the brick will not heat up suddenly to lose the heat insulation effect. The test bricks have different thicknesses, structures, and sunshine times; however, the temperature difference of the upper surface of the bricks is at least larger than 54°C, meaning the influence of the brick structure on the upper surface temperature is not obvious. The structure of brick with vents and the sandwich design of one layer of EPS between two pieces of PCM can control the lower surface temperature of bricks at 25°C~32°C (temperature difference is 7°C). This temperature approximates the comfortable temperature for the human body.