Today I Learned: Bladeless Fan

Bladeless fans elude me. Whenever I saw one at the department store, or someone's house, for some reason, I am wary that there is vacuum somewhere at the top. I felt...the same way I first heard Hugh Jackman sing. He has retractable claws and he can sing??? So I thought I'd find out how it actually works. Bladeless fans, I mean, not Hugh Jackman.

This video explains very clearly how it works:

The term bladeless fan would be inaccurate, as it does have blades, just that the blades (or vanes) are hidden in the its base. Apparently bladeless fan is also known as air multiplier.

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When we turn on the fan, the blades (at the base or the pedestal stand) will turn and suck in air from the environment. Air from the surrounding environment gets entrained (sucked along) and the amount of air is amplified. The air is then shot out through a slit at the edge of the ring. The curvature of the inner wall creates an area of negative pressure, thus drawing air flow from the back of the ring, further multiplying the air flow. The air flow again entrains air from the environment as it flow out of the ring, multiplying the air flow. According to Dyson the fan multiplies the air entering the base of the fan by at least 15 times.

Photo source

Due to the nature of how a bladeless fan works, the air that it produces flow smoothly, as compared of turbulent flow of a conventional fan. A traditional fan pulls in air and chops it up, with each blade sending a slice of air towards you at high velocity, which creates a turbulent and forceful airflow.