Paper 6
Effects of Intermittent Air Velocity
on Thermal and Draught Perception During Transient Temperature Conditions
Hans
Wigö
University
of Gävle, Centre for Built Environment, Sweden
Abstract
Previous research has
shown that air movement has a significant influence on humans’ thermal
comfort. For persons feeling cool, air movement tends to be perceived as
draught, whilst when feeling warm air movements may provide a desired
cooling effect. In the transition zone it therefore seems difficult to use
constant air velocity as a tool for cooling without creating draught
problems. Nevertheless, from an energy saving perspective it appears to be
far more efficient to use enhanced convective cooling, induced by the air
movement, to cool only the occupants instead of the entire building. One
possible way to use air movement as a method to improve thermal comfort
without resultant draught problems could be to use intermittent air
velocity instead of constant velocity. The present paper reports results
from three experiments where subjects have been exposed to velocity
variations, showing support for the hypothesis that it is possible to cool
humans and reduce the percentage of occupants who are dissatisfied with
the room temperature, without creating draught problems, through
intermittent cooling.
Key words: thermal
comfort, human cooling, draught perception, velocity variations,
intermittent air movement, convective cooling.
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