A new plenum-based dual-mode passive cooling system enabling naturally ventilated core zones in office buildings

초록

This study introduces a novel plenum-based passive cooling system designed to provide ventilation for core zones that lack direct exposure to the outdoor environment. The system harnesses both buoyancy-driven and winddriven forces depending on the outdoor wind conditions. Its performance was evaluated through computational fluid dynamics (CFD) simulations conducted in Fluent 2024 R2, employing a Reynolds-Averaged NavierStokes (RANS) model with the SST k-omega turbulence model. The results showed that under buoyancy-driven conditions (0.5m/s), airflow induced by temperature differences reduced the core zone mean air temperature from the baseline of 29.64 degrees C to 25.66 degrees C, decreasing thermal comfort violations. Under wind-driven conditions, however, bypass airflow within the plenum was observed, indicating the necessity of opening control strategies to achieve optimal performance. When an opening control strategy was applied at a 3 m/s wind speed, the indoor temperature was further reduced from 29.64 degrees C to 23.55-24.28 degrees C, while maintaining acceptable local airflow conditions. These findings highlight the potential of the proposed system to effectively serve as a viable passive cooling for improving core zone thermal comfort and reducing reliance on mechanical cooling in office buildings.

키워드