Air multiplier

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The Dyson Air Multiplier

An air multiplier, sometimes called bladeless fan, is a fan which blows air from a ring with no external blades. Its vanes are hidden in its base and direct the collected airflow through a hollow tube or toroid, blowing a thin high-velocity smooth airflow from holes or a continuous slot across the surface of the tube or toroid.


The first concept was created by Toshiba in 1981.[1] Industrial designer James Dyson named his fan the air multiplier.[2]


In the air multiplier fan, there are no visible moving or fast-spinning blades; instead, blades are hidden inside the base. The air is drawn in by a compressor in the base and then directed up into a ring. It comes out of a slit around the ring and passes over a shape like that of an aircraft wing (Coandă effect). This design generates airflow up to 55 miles per hour (25 m/s).[3]

The fan contains a brushless electric motor and this motor rotates nine asymmetrical aligned blades that attach with a rotor. Usually, the upper frame of this fan is ring-shaped. The frame is not flat; rather it is manufactured such that the edge can create a curve of a 16-degree angle slope.

The air flows through the channel in the pedestal of the fan when the motor is turned on. After that, the air flows through the hollow tube. Then the air is shot out through 16-mm slits. This air flows smoothly, rather than turbulently as with a traditional fan (fan with blades). The curvature of the inner wall of the fan creates an area of negative pressure like an airplane wing to draw more air into the flow, hence "multiplying" it. This action is called inducement. Further, the air surrounding the edges of the fan also begins to flow with the direction of the breeze or is "entrained" to it. Dyson says that the air-multiplier technology increases the output of the air flowing through the tube by at least 15 times compared to the airflow taken in at the base of the fan.[4]


The Spanish consumer advocate Organización de Consumidores y Usuarios tested Dyson's first Air Multiplier (AM01) and remarked on the further-reaching and stabler stream. It was found to use 40W and move 2700m³/h at its maximum setting. However, it was noisier and much more expensive (€300–€400 versus €20) than bladed fans.[5] Another test found the AM01's power consumption to be variable between 2-3W and 31W.[6] performed airflow, noise level, and power measurements on the AM06 and, aside from the first setting, was found to achieve similar levels of air speed and air volume moved per second while being quieter (2–10dB) and more energy efficient per volume of air moved (6–3×) depending on the setting.[7] The highest setting reportedly produced 1150ft³/min (1950m³/h) and 548ft/min (2.7m/s). The volume was on par with an $80 regular fan and about twice as much as a $15 regular fan, while the air speed was roughly on par with both. At this setting, the AM06 produced 10dB less noise than either regular fan and used 20W, versus 60W and 40W used by the regular models. It concludes that while "there is more to the air multiplier than a bit of fancy plastic", "this data probably won’t convince anyone to buy a Dyson AM06". "The Dyson is for doctor’s offices, executive suites, and other places where air flow is nice to have, but design is paramount."



  1. ^ "Dyson fan: was it invented 30 years ago?". Telegraph. Retrieved 2014-01-09.
  2. ^ "Sir James Dyson explains his bladeless fan". YouTube. Retrieved 2014-01-09.
  3. ^ "How Does the Dyson Air Multiplier Work?". Jameco. Retrieved 2017-01-27.
  4. ^ "How the Dyson Bladeless Fan Works". HowStuffWorks. Retrieved 2017-01-27.
  5. ^ "Air Multiplier, un ventilador sin aspas". (in Spanish). Organización de Consumidores y Usuarios. 16 July 2012. Retrieved 23 May 2020.
  6. ^ Jeremy Cole (12 April 2013). "Power consumption of Dyson Air Multiplier (AM01)".
  7. ^ Sal Cangeloso (10 April 2014). "Best desk fan: Dyson vs Vornado vs Honeywell". Archived from the original on 2020-04-26.
  8. ^ "The Bladeless Air Generator "Q"". Panasonic Key Technologies. Panasonic Newsroom Global.