Fan Definition and 347 Threads

A fan is a powered machine used to create a flow of air. A fan consists of a rotating arrangement of vanes or blades, which act on the air. The rotating assembly of blades and hub is known as an impeller, rotor, or runner. Usually, it is contained within some form of housing, or case. This may direct the airflow, or increase safety by preventing objects from contacting the fan blades. Most fans are powered by electric motors, but other sources of power may be used, including hydraulic motors, handcranks, and internal combustion engines.
Mechanically, a fan can be any revolving vane, or vanes used for producing currents of air. Fans produce air flows with high volume and low pressure (although higher than ambient pressure), as opposed to compressors which produce high pressures at a comparatively low volume. A fan blade will often rotate when exposed to an air-fluid stream, and devices that take advantage of this, such as anemometers and wind turbines, often have designs similar to that of a fan.

Typical applications include climate control and personal thermal comfort (e.g., an electric table or floor fan), vehicle engine cooling systems (e.g., in front of a radiator), machinery cooling systems (e.g., inside computers and audio power amplifiers), ventilation, fume extraction, winnowing (e.g., separating chaff of cereal grains), removing dust (e.g. sucking as in a vacuum cleaner), drying (usually in combination with a heat source) and providing draft for a fire.
While fans are often used to cool people, they do not cool air (electric fans may warm it slightly due to the warming of their motors), but work by evaporative cooling of sweat and increased heat convection into the surrounding air, due to the airflow from the fans. Thus, fans may become ineffective at cooling the body if the surrounding air is near body temperature and contains high humidity. A fan blade is generally made of wood, plastic, or metal.
Fans have several applications in the industries. Some fans directly cool the machine and process, and may be indirectly used for cooling in the case of industrial heat exchangers.
These are critical machines and responsible for operating the entire plant, which may shut down without the proper fan. In mine and tunnel, it also used as safety equipment.

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Recent contents Top users
  1. A

    Calculating the velocity and pressure profiles across an axial fan

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  2. prashantakerkar

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  3. eudesvera3

    Paradox of a convergent nozzle fed by an electric fan

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  4. M

    Which fan/pipe combination is the most efficient?

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  5. L

    I Dust Accumulation on Fan Blades and Elsewhere

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  6. A

    How to ventilate a room with no windows with one inline fan?

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  7. Metahedron

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  8. hyunxu

    B Understanding the Physics of a Ceiling Fan: Basics & Beyond

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  9. R

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  10. A

    Automotive Two small fan motors one rotates faster when other is jammed

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  11. B

    Ceiling fan and impact force on the blades

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  12. B

    B Adding a nacelle in front or behind the fan?

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  13. STAR GIRL

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  14. Berg88

    Fan Current to Speed (Percentage)

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  15. H

    How to choose a fan for open circuit wind tunnel?

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  16. Altiano

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  17. Wrichik Basu

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  18. marcoravelli

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  19. J

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  20. G

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  21. M

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  22. C

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  23. JOSEPH JAMES

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  24. D.B.SriHridai

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  25. V

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  26. longz

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  27. UsableThought

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  29. Nantes

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  30. I

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  31. E

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  32. manik hossain

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  33. R

    How to calculate air volume of a fan using pressure?

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  34. M

    Can DC Fans Operate Effectively in High-Humidity Conditions?

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  35. D

    Voltage divider not working for fan

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  36. 7see

    Why we used capacitor in the fan ?

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  37. kolleamm

    B Would a smaller fan blade be more efficient?

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  38. scotty c

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  39. T

    Electric Fan, when Not Spinning, gets Hot?

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  40. T

    CFD Modeling of a Jet Fan Parking Exhuast Ventilation System

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  41. B

    What's the purpose of front white cap that desk fans have?

    Every desk fan has it. What's the purpose of the white cap attached to the front fan grille?
  42. N

    What is more effective -- Current or Voltage?

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  43. T

    Where to place a fan along a duct?

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  44. Iconoclast

    Function of the air conditioner fan outside?

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  45. I

    Is the Power Expended by a Fan Cart Constant?

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  46. M

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  47. V

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  48. D

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  49. P

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  50. D

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