Modelling supply devices in order to predict improvements in internal air quality.

The air distribution effects of floor mounted swirl diffusers are investigated and described inthis paper. Results are based on a case study of an office typical of those in urban commercialenvironments. The effects of the swirl applied to the supply air as well as temperaturedifferentials between supply and room air are explored. The investigation is restricted tosituations where cooling is required.The results of the work, which is undertaken by way of CFD analysis, are presented in termsof appropriate ventilation effectiveness parameters. It is observed that variations to the formof swirl devices, changes to temperature differentials and the presence of internal heat sourcescombine to affect the internal air distribution to such an extent that its nature may vary fromdisplacement to characteristics approaching those of mixing systems. Air quality at head levelcan change from very good to poor in reponst to relatively small changes in some of theparameters.