International Scientific Journal

Thermal Science - Online First

online first only

A new method for evaluating the joint effect of draught and the hot ceiling

For buildings with ceiling heating and mechanical ventilation, it is extremely important to know the combined effect of the draught and the radiant thermal asymmetry caused by a warm ceiling. There is plenty of literature offering separate descriptions of the dissatisfaction caused by draught and warm ceilings, but research on the combined effect of these two local discomfort factors is incomplete. In order to fill in this gap, human subject measurements were conducted involving 20 subjects, 10 men and 10 women, who were asked to complete questionnaires on thermal sensation, while being exposed to a random combination of 5 asymmetries and 2 draughts. Analyzing the results obtained this way made it possible to evaluate the combined effect of the draught and radiant thermal asymmetry on thermal comfort. The most important outcome of the research is the mathematical description of the expected dissatisfaction rate and the presentation of the differences depending on gender.
PAPER REVISED: 2020-02-09
PAPER ACCEPTED: 2020-02-14
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