Find Answer: How Does a Fan Work?

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    Fan Mechanism
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Discussion Overview

The discussion centers around the mechanics of how a fan operates, specifically focusing on the interaction between the fan blades and the air they move. Participants explore the principles of airflow, forces, and vector dynamics involved in the operation of fans and propellers.

Discussion Character

  • Exploratory, Technical explanation, Conceptual clarification

Main Points Raised

  • One participant seeks clarification on how a fan's rotation leads to air movement, noting the involvement of vectors.
  • Another participant explains that normal forces are perpendicular to the surface of the fan blades, suggesting that this interaction accelerates air molecules perpendicularly to the blade's plane.
  • A different participant mentions the presence of a slight helical rotation in the airstream produced by the fan, which is often overlooked.
  • Another contribution discusses how the twist in the fan blades causes a change in air direction, resulting in a reaction force on the fan itself, drawing a parallel to the aerodynamic principles of airplane wings.

Areas of Agreement / Disagreement

Participants present multiple perspectives on the mechanics of fan operation, with no consensus reached on a singular explanation. Various models and interpretations of the airflow and forces involved are discussed.

Contextual Notes

Some assumptions about airflow dynamics and the specific mechanics of fan blade design are not fully explored, leaving certain aspects of the discussion open to interpretation.

Who May Find This Useful

Individuals interested in fluid dynamics, mechanical engineering, or the principles of aerodynamics may find the discussion relevant.

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.
 

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