Alternative! stratified air distribution designs in a terminal building

In modern buildings with high ceilings and large floor areas, large areas of fenestration admit large solar heat gains, making the buildings' energy consumption considerable. In addition, occupants may also suffer from glare due to direct solar radiation and feel overheated. This paper numerically studies two typical air distribution designs that can realize thermal stratification in a hypothetical terminal building. A novel energy efficiency index for stratified air distribution systems is developed. The results indicate that with additional supply diffusers installed at opposite location, collision regions of the two supply airstreams are formed and special attentions should be given to those regions to avoid un-comfortable local drafts. As the solar radiation intensity enhanced, the energy efficiency increased in both typical air distribution designs. However, the undesired temperature gradient in the region exposed directly to the solar radiation also increased when the air is supplied at floor level.