Undergrad Ceiling fan pressure increase or decrease

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A ceiling fan does not significantly alter air pressure in a room, as it primarily creates internal airflow. The pressure around the fan decreases before it and increases afterward, but these changes are minimal and average out across the room. In a typical room connected to the exterior, pressure remains stable due to equalization with the outside atmosphere. However, in a hermetically sealed and insulated space, a fan could raise the internal temperature, causing air expansion and an increase in pressure. Overall, the impact of a ceiling fan on air pressure is negligible in most scenarios.
singhsshub
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Would air pressure increase or decrease due to a ceiling fan in a room?
 
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Neither, this is internal flow. The pressure directly around the fan will decrease (before the fan) and increase (after the fan) somewhat, this pressure smears out to miniscule amounts in other parts of the room. But on average the pressure stays the same.

Also, the room is usually connected to the exterior atmosphere, which equalizes the pressure.
 
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singhsshub said:
Would air pressure increase or decrease due to a ceiling fan in a room?
If the room was a hermetically sealed box, with an internal fan, then the internal air would be warmed by the turbulence generated by the fan. The warmer air would expand, so pressure would increase.
 
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Not just hermetically sealed, but also perfectly insulated, but yeah, nicely found :)
 
Arjan82 said:
Not just hermetically sealed, but also perfectly insulated, but yeah, nicely found :)
It wouldn't need to be perfectly insulated. Certainly that would maximize the effect, but a regular closed room could still be heated sufficiently to cause the expansion effect temporarily. Lots of typical home appliances can produce sufficient heat to raise the temp of a closed room noticeably.
 
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