Sir James Dyson explains his bladeless fan

[SystemRat]

A very interesting design. The claim is a 16 x increase in wind speed / volume. If the motor providing the initial 1 x air flow uses 40 watts of power the where is the energy needed for the 16 x increase drawn from ?

Pity it's so expensive might have to wait for a Chinese knock off.

[ame=http://www.youtube.com/watch?v=8he8afjQyd8]YouTube - Sir James Dyson explains his bladeless fan[/ame]

[iwacelect]

thanks for that rat, I'd seen the fan only days ago and was wondering how it works

good find mate

[ssrattus]

A very interesting design. The claim is a 16 x increase in wind speed / volume. If the motor providing the initial 1 x air flow uses 40 watts of power the where is the energy needed for the 16 x increase drawn from ?

Pity it's so expensive might have to wait for a Chinese knock off.

He gets 16 times increase due to the pressure difference, ie the pressure at the small impeller is much higher and the volume is drawn from the surroundings. I think you see a similar affect in turbofan engines that has a bypass air path that greatly increase the thrust, but I may be off track here.

Note that the impeller is 40 W, a regular table fan is 10 to 25 watts! I wonder how noisy it is?

He also perpetuates the myth that an aircraft flies due to the curved surface of the wing, this is bullshit that has been taught at schools for years. If it were true how can an aircraft fly upside down! Lift is due to the angle of attack of the wing.

[nerd1]

thought I have read elsewhere that this fan is really noisy. dont recall where this was from :/

[Gerbertron]

so this is just an air duct he's calling a fan?

[ssrattus]

Unfortunately, the downside of the Dyson method is that you can't make Darth Vader voices through the backside of the fan, and the whole assembly is closer in noise pollution to that of an actual vacuum cleaner than a regular table fan. And then there's the matter of price: $300 for the 10-inch model, $330 for the 12-inch, and neither of them offer nearly as much wind as a regular fan this size -- quite a steep entry fee for the gentle breezes that emanate out of this plastic wind tunnel. Full PR is after the break.

[coalminer]

a similar device has been used for donkey years in mining to blow air
we called them venturi blowers

[unique]

See Link

[Skepticist]

A practical? domestic application of the Coanda Effect which is based on Bernoulli's Principle. The curiosity factor should ensure this will be something of a success initially but it will never usurp the humble bladed fan for the masses due to affordability and reliability factors. I'd be more impressed if he'd managed to achieve this with no moving parts at all.

[gordon_s1942]

doesnt a Breeze achieve this same effect without using power and no moving parts ?

[BCNZ]

Note that the impeller is 40 W, a regular table fan is 10 to 25 watts! I wonder how noisy it is?

I've seen two of them in operation now. They're amazingly quiet. Rather than the 'chopping' sound a conventional fan makes due to the blades 'whipping' the air, this Dyson offering simply has a quiet 'ssshhhhhh' sound. I was quite impressed.
Not impressed enough though to suddenly flop out the credit card and say "give me one NOW damnit!"

I'd be more impressed if he'd managed to achieve this with no moving parts at all.

Now there's a challenge. How to move air with no moving parts.

[roolette]

Wow. Interesting. If this ever takes off and becomes more mainstream I may get one for myself. So much less hassle compared to fans with blades, and who can complain about the minimalist look.

[sat_brat]

Wow. Interesting. If this ever takes off and becomes more mainstream I may get one for myself. So much less hassle compared to fans with blades, and who can complain about the minimalist look.

I think it would need to be far more powerful to actually take off!

couldnt resist!
Cheers