Numerical study on cooling performance of a ventilated Trombe wall with phase change materials.

This study aims to evaluate thermal performance of a new ventilated Trombe wall integrated with phase change materials (PCMs-VTW). Double PCM wallboards are embedded in the building facade for different purposes, i.e. exterior PCM wallboard is to store natural cooling energy via night-time ventilation, and interior active PCM wallboard is for radiant cooling. Melting temperature and latent heat of PCM have been discussed for PCMs-VTW system from 1st August to 7th August in Changsha, China. Also, high-reflective coating is coated on the exterior PCM wallboard for reflecting solar radiation, thus ameliorating daytime overheating. Nighttime ventilation is for natural cooling energy storage via regenerating solid exterior PCM wallboard. The obtained result shows that under the weather condition in Changsha, melting temperature 22 °C for interior PCM and the latent heat 176 kJ/kg for exterior PCM show considerable benefit for cooling energy release. Compared with the classical Trombe wall system, annual cooling energy consumption is decreased by 20.8% and by 18.6% in the PCMs-VTW system when indoor air temperature is kept at 22 °C and 24 °C respectively. Our research has provided scientific evidences for potentials provided by PCMs-VTW system in reducing building energy consumption and improving indoor thermal comfort via exploiting natural cooling energy, mitigating overheating at summer condition and utilizing cold sources in high temperature. [ABSTRACT FROM AUTHOR]