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downdraft, Brit. downdraught

1. A downward current of air in a chimney or flue, often carrying smoke with it.
2. A downward current of air resulting from the passage of air across a window surface, which cools it and increases its density so that it moves downward.
McGraw-Hill Dictionary of Architecture and Construction. Copyright © 2003 by McGraw-Hill Companies, Inc.
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can hay but it "The gusts can lift deposited pollen from surfaces and the downdraughts can bring pollen down from higher levels in the air where it has been lifted by convection currents," said Dr Emberlin.
But Dr "The gusts deposited surfaces and downdraughts bring pollen higher levels where it has by convection currents," Emberlin.
Overall, for YSU PBL, the scale of the downdraughts circulations is smaller, the form of convection is less cellular, and the intensity of the convection is weaker.
The hot air rises and the flow is maintained upward, thus avoiding downdraughts. The velocity magnitude in the rest of the room is very low (0.1-0.2 m/s) and will not cause any discomfort to the occupants sitting near the facade (0.5 m away or further).
Larsson and Moshfegha (2002) investigated the effect of thermal performance, window bay, and displacement ventilation on the downdraught and showed that well-insulated windows may result in reduced air velocity and turbulence intensity.
Experimental investigation of downdraught from well-insulated windows.
This indicates that the updraught regions were narrower than the downdraughts. Similar patterns could be seen from the other flight tracks (not shown).
Wind speed anomalies in downdraughts were larger than in updraughts.