Find Answer: How Does a Fan Work?

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    Fan Mechanism
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A fan or propeller rotates sideways while directing air perpendicularly to its motion, involving vector dynamics. The normal forces acting on the fan blades accelerate air molecules in a direction perpendicular to the wings, resulting in a slight helical airflow that is often overlooked. The twist in the fan blades changes the direction of the air, generating a reactive force on the fan itself. This principle mirrors how airplane wings create lift by deflecting air downward, resulting in an upward force. Understanding these dynamics is crucial for comprehending the mechanics of fans and propellers.
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can anybody help me to find the answer of this question?

a fan ( or a propellor) rotates sidewise, but the air goes making a perpendicular with the axis of its motion.. I know that there is vector involved in this, but how does it work?
 
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Normal forces are perpendicular to the surface, so whenever a fan wing hits a molecule, it accelerates it in the direction perpendicular to the plane of the wing.
 
So there is a slight hellical rotation in the fan airstream which is generally ignored.

Ken
 
The twist in the fan's "arm" make the air change direction when moving. This change of direction creates a reaction on the fan itself. This reaction acts as a force on the whole device.

If you want, the process is the same as for planes flying. The air passing under the wing of the plane is deviated downward, creating a force upward on the wing.
 
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