Find Answer: How Does a Fan Work?

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    Fan Mechanism
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SUMMARY

A fan operates by rotating its blades, which create a change in air direction, resulting in airflow that is perpendicular to the axis of rotation. The interaction between the fan blades and air molecules generates a slight helical rotation in the airstream, which is often overlooked. This principle mirrors the aerodynamic forces experienced by airplane wings, where air is deflected downward, producing an upward lift. The twist in the fan blades is crucial for altering the air's trajectory and generating the necessary reaction force on the fan itself.

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aberrated
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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.
 
I do not have a good working knowledge of physics yet. I tried to piece this together but after researching this, I couldn’t figure out the correct laws of physics to combine to develop a formula to answer this question. Ex. 1 - A moving object impacts a static object at a constant velocity. Ex. 2 - A moving object impacts a static object at the same velocity but is accelerating at the moment of impact. Assuming the mass of the objects is the same and the velocity at the moment of impact...

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