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In recent years, computational fluid dynamics (CFD) has been widely used as a method of simulating airflow and addressing indoor environment problems. The complexity of airflows within the indoor environment would make experimental investigation difficult to undertake and also imposes significant challenges on turbulence modelling for flow prediction. This research examines through CFD visualization how air is distributed within a room. Measurements of air temperature and air velocity have been performed at a number of points in an environmental test chamber with a human occupant. To complement the experimental results, CFD simulations were carried out and the results enabled detailed analysis and visualization of spatial distribution of airflow patterns and the effect of different parameters to be predicted. The results demonstrate the complexity of modelling human exhalation within a ventilated enclosure and shed some light into how to achieve more realistic predictions of the airflow within an occupied enclosure. [ABSTRACT FROM PUBLISHER]

Vertical greening solutions such as direct greening are gaining popularity due to their relatively low cost and minimal ground footprint. However, concerns about increases in relative humidity (RH) can reduce implementation. The impact of several widely-used plant species (Hedera helix, Parthenocissus tricuspidata and Pileostegia viburnoides) on the internal/external temperature and RH on the south-facing wall of replicated experimental model 'buildings' was studied during summer and winter. All plant species reduced the air temperature internally/externally during the summer daytimes by at least 1 °C compared to bare 'buildings'. Hedera produced the greatest cooling effect internally and externally, by 7.2 °C and 5.7 °C respectively. All plant species reduced daily variation in external RH and external/internal temperature during summer; Hedera reduced variation most and Pileostegia least. During night-time in both seasons, the temperature behind Hedera foliage typically remained higher, which could reduce the risk of freeze-thaw damage in winter. The RH was not significantly elevated by vegetation except during warm afternoons in summer and winter. During warm afternoons, the external RH was significantly higher only behind the Hedera foliage compared to the bare 'buildings', 11% and 3.7%, summer and winter respectively. However, inside all vegetated 'buildings' the RH was at least 11% higher compared to the bare 'buildings' during summer. Yet, in winter the internal RH was 5.7% lower in the Hedera -covered compared to the bare 'buildings'. Current building standards would prevent the transfer of external RH in this range internally, as the walls include protective layers such as damp-proof membranes. • Best summer cooling provided by ivy (Hedera sp.) • Greatest summer reduction in daily variation of RH and temperature behind ivy. • Difference in internal/external RH behind foliage only found during warm afternoons. • During warm winter afternoons, RH was 5.7% RH lower inside ivy-covered compared to bare 'buildings'. [ABSTRACT FROM AUTHOR]