Natural ventilation design mix for elementary school classrooms

Computational fluid dynamics (CFD) simulations were conducted to investigate how the six natural ventilation design mixes, ie, double roof, covered ridge with sidewall opening (CRSO), roof ridge opening and window's layout influence indoor thermal environment especially during the summer season when outdoor wind velocity is low. Furthermore, this research demonstrates how these design mixes can improve the natural ventilation performance of elementary school classrooms. Results show that when collocating with double roof, roof ridge opening and CRSO, both the ventilation performance and the thermal comfort of classrooms are improved despite the staggered room adaptation (high-low) or the conventional window layout. Staggered windows can enhance the buoyancy ventilation effect and compared with conventional windows, can enhance the air exchange rate about 1.21 (1/h), which is equivalent to more than 1.5 times.