Diffuse ceiling ventilation is a novel air distribution device that combines the suspended acoustic ceiling with ventilation supply. A diffuse ceiling distributes the supply air above the acoustic tiles and has proven performance in laboratory experiments. To study the performance in real conditions a classroom was retrofitted with mechanical ventilation and a diffuse ceiling. The employed ceiling comprises active panels penetrable to air and impenetrable passive panels. The performance was studied with regard to air movements, temperatures and air change efficiency at two different air changes. The experiments were carried out during class to obtain realistic conditions. At both airflows did the ceiling perform satisfactorily with air movements and temperatures within the requirements of indoor climate standards. The air change efficiency is comparable to conventional mixing ventilation.
Diffuse ceiling ventilation; Ventilation efficiency; Ventilation; Draught rating; Tracer gas