Application of a Thermal
Manikin to Evaluate Heat Loss Rates from People caused by Variations in
Air Velocity and Air Temperature
Hans
Wigö and Håkan O Nilsson
University
of Gävle, Centre for Built Environment, Gävle, Sweden
Abstract
Heat loss monitoring from
a thermal manikin was undertaken representing an occupant in a classroom
during a lesson period of 80 minutes in which the room temperature was
increased from 21 to 24°C
for various airflow velocity configurations. A group of subjects
was exposed to various conditions of temperature and airflow rate so that
the impact of these variations on their surface/skin temperature could be
determined. It was found that skin temperature
remained stable and close to 34°C for all conditions of exposure.
Thus, over the temperature and air velocity range considered, these
new findings verified the suitability of using a thermal manikin, set to
steady uniform surface temperature, to determine the heat loss
characteristics from occupants subjected to intermittent velocity
variation. When
the manikin was exposed to a high velocity pulse, the heat loss from the
whole body increased by 10% while the heat loss from exposed areas (hands
and face) increased by 20 % (when compared to no velocity pulse). After
the 80 minutes monitoring period, the total energy loss from a manikin
exposed to velocity variations was 2% higher than when exposed to constant
low velocity.
Key words: School
ventilation, thermal comfort, adaptive comfort, occupant monitoring,
thermal manikin.
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