Re:Dyson has scrapped its electric car project
by dpark on Friday October 11, 2019 @04:53AM
(#21222618)
> Because it's 2.5 kilowatt blower making 78 dB of noise, according to the technical spec under that link. With these parameters, you should be able to dry your hands in 5 seconds while keeping them a meter away.
This is a really bizarre statement. You throw some numbers up and then say “obviously it should work how I said”. But it’s not obvious at all. Those numbers don’t intuitively tell me that it should my hands in 5 seconds. Indeed my intuition (and that manufacturer’s specs) says that’s wildly inaccurate.
I’m really confused by your “1 meter away” claim. At a meter away you’re basically just waiting for ambient air to dry your hands. The fact that they measure decibels a meter away doesn’t mean that’s where your hands should be.
Re:Dyson has scrapped its electric car project
by TeMPOraL on Friday October 11, 2019 @10:20AM
(#21224595)
My statement is this: I've used a sub-2kW blower that could dry hands in below 10 seconds, was loud but not painful, and if you somehow made it portable, it could double as a leaf blower in a pinch. 1 meter from the nozzle the stream was still powerful enough to dry hands faster than ambient air. So the numbers people throw around this thread are weird, they imply unrealisticly wet hands, or ridiculously inefficient dryers.
Re:Dyson has scrapped its electric car project
by dpark on Friday October 11, 2019 @03:35PM
(#21227674)
I think the fact that your numbers are so much drastically lower than the manufacturer’s numbers indicates that your numbers are not representative of the typical experience. Maybe you can dry your hands in five seconds with the typical air dryer. It’s clearly not true for most people. Maybe you shake your hands extremely dry before going to the dryer. Maybe after using the dryer your hands are still wet and clammy. I don’t know. Your experiences are clearly not reflective of the typical case, though.
Because it's 2.5 kilowatt blower making 78 dB of noise, according to the technical spec under that link. With these parameters, you should be able to dry your hands in 5 seconds while keeping them a meter away. Like with the one I mentioned seeing in that McDonald's, which was AFAIR rated at something around 1.2 kW (and I remember thinking that's already impressive for a hand dryer).
> Slow blowing warm air isn’t going to dry that off in 5 seconds.
But fast blowing, slightly less warm air would.
I was subtly suggesting that the reason may be what 'carlmr mentioned in a parallel reply - maybe people don't shake off the water after washing their hands, preferring instead to both waste their time at the dryer and add work to the cleaning stuff that now has extra water to mop off the floor?