Paper 7
Quantifying the Cooling Sensation of
Air Movement
Richard
Aynsley
Big Ass Fan
Company,
Lexington
,
KY
,
USA
Abstract
A number of methods have been used to quantify the
cooling effects of air movement on the human body. For simplicity these
methods limit the number of variables influencing the effect.
A new method using the difference in Standard Effective Temperature
(SET*) values between a condition with 29.5 fpm (0.15 m/s) and the
proposed elevated air speed allows all the relevant variables (i.e. air
temperature, mean radiant temperature, air speed, humidity, metabolic
rate, and clothing insulation) to be taken into account. Cooling effect of
air movement is normally based on uniform velocity airflow.
Research indicates that gusting airflow with a frequency around 0.5
Hz increases the cooling effect. Uniform
air speeds with an equivalent cooling effect to 0.5 Hz gusting airflows
are provided for low air speeds.
Key words: thermal
comfort, human cooling, cooling fans.
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