Integrated Phase-Change Materials in a Hybrid Windcatcher Ventilation System

Windcatchers are effective passive ventilation systems, but their inability to actively reduce and stabilize supply air temperatures reduces indoor cooling performance. This study addresses this limitation by integrating encapsulated phase-change material tubes (E-PCM-Ts) into a solar fan-assisted, multidirectional windcatcher. The novelty lies in the vertical placement of E-PCM-Ts within the windcatcher’s airstreams, enhancing heat transfer and addressing challenges related to temperature stabilization and cooling. Using computational fluid dynamics (CFD) under hot outdoor conditions, the ventilation, cooling, and PCM thermal storage performance are evaluated based on two different E-PCM-T arrangements. Results showed a maximum air temperature drop of 2.28 °C at a wind speed of 1.88 m/s and wind angle of 0°. This offers an optimal temperature reduction that achieved a 6.5% reduction for up to 7 h of air temperature stabilization. Placing E-PCM-Ts in all airstreams improved the thermal storage performance of the windcatcher. A 50% increase in hybrid ventilation efficiency was also achieved when wind angles increased from 0° to 30°. Overall, the proposed system demonstrated superior performance compared to that of traditional windcatchers, delivering improved thermal energy storage and cooling efficiency and adequate hybrid ventilation with supply air velocities of 0.37–0.60 m/s.