Psychological impact of air velocity variations in a ventilated room

Abstract

Two experiments investigated the psychological impact of two velocity conditions (constant low velocity (V1) and variations of low and high velocity (V2)) in two temperature conditions (Experiment 1: an air temperature increase from 21°C to 24°C; Experiment 2: an air temperature increase from 25°C to 27°C) in females and males, aged 16 to 18 years, under realistic classroom conditions during an exposure period of 80 min. It was predicted that the V2 room condition compared to the V1 room condition would be more beneficial for subjects' perceived room temperature and air quality, self-reported affect and cognitive performance. The results obtained showed no significant effects on cognitive performance. However and as predicted, in Experiment 1, the subjects in the V2 compared to those in the V1 room condition felt that the air temperature decreased (while it de facto increased) and reported a constant level of high activation. In Experiment 2, the subjects in the V2 room condition felt that the air temperature increased less and reported that their unactivated unpleasantness increased less and activated pleasantness decreased less than it did for subjects in the V1 room condition. All this indicates, as was suggested by Wigö et al. (2002), that a cooling effect, induced by air velocity variations, might be beneficial for subjects in a ventilated room and that their perceived pleasantness of the indoor climate could be met at a higher room temperature than otherwise.

Keywords:

• Velocity variation
• Perceived temperature
• Draught
• Self-reported affect
• Transient temperature

Acknowledgements

This work was financed by the ELAN programme and SISAB. The ELAN programme is a joint research programme on electricity utilization and behaviour in a deregulated market. The ELAN programme is financed by the Swedish Energy Agency, the Swedish research council Formas and Swedish utilities through Elforsk. SISAB owns and manages the majority of Stockholm's school buildings.

The authors would like to thank Terry Hartig and the two anonymous reviewers for their valuable comments.