Integrating interlayer ventilation into phase change walls: Comprehensive performance and optimization in summer

Abstract

Integrating phase change materials (PCM) into building walls can improve the thermal performance of walls. However, phase change walls (PCW) in hot climates have poor thermal performance during nighttime due to the exothermic process of PCM. In this work, we proposed a novel PCW integrating with interlayer ventilation (IVPCW), which is innovative for all-day availability. Its comprehensive performance analyses and optimization were conducted. The results indicate that utilizing interlayer ventilation improved the comprehensive performance of the PCW. Moreover, the optimal phase change temperature range is [28 °C, 34 °C], the optimal phase change layer thickness is 30 mm, the optimal air delivery method is method 2, and the optimal air layer thickness is 50 mm. The average daily cooling load of IVPCW with the optimal parameter was 126.08 kJ/m2 during the cooling-season week, which was 43.7 % lower than the pre-optimization. Long-term performance analyses conclude that IVPCW can effectively reduce the cooling load, electrical cost, and CO2 emissions of air conditioning systems, which were 75.0 % lower compared with the ordinary wall (OW) and 59.1 % lower compared with PCW. In summary, IVPCW has a superior energy-saving and carbon-reducing performance to OW and PCW. This study established a theoretical foundation for the engineering implementation of IVPCW.