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Author Topic: Why and How is there dust on Fan Blades ?  (Read 8356 times)

Offline neilep

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Why and How is there dust on Fan Blades ?
« on: 02/01/2006 15:34:27 »


Despite having fans on ALL the time, why does dust still accumulate on the front of the fan blades ?  and how does it get a grip  there ?

It's pushing air away !!

Answering this should be a breeze !!...please :)

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Offline daveshorts

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Re: Why and How is there dust on Fan Blades ?
« Reply #1 on: 02/01/2006 15:52:00 »
It may be a static thing - if the fan blades are the right plastic they will probably charge up rubbing againsta ll that air. So the dust sticks to it...

Kitchen fans get covered with grease so are sticky, and the dust proabbly sticks to that...
 

Offline neilep

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Re: Why and How is there dust on Fan Blades ?
« Reply #2 on: 02/01/2006 16:07:29 »
DOH !!...Thanks Dave..the static explanation sounds obvious now. For the record the fans are bedroom fans , so there's no sticky grease from kitchen muck. Though, I have experienced a sticky fan blades like that...yucky !

Many Thanks

ps: Love the planet/gravity simulators on your web site.



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« Last Edit: 02/01/2006 16:12:31 by neilep »
 

another_someone

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Re: Why and How is there dust on Fan Blades ?
« Reply #3 on: 02/01/2006 16:39:58 »
quote:
Originally posted by neilep

DOH !!...Thanks Dave..the static explanation sounds obvious now. For the record the fans are bedroom fans , so there's no sticky grease from kitchen muck. Though, I have experienced a sticky fan blades like that...yucky !

Many Thanks




While perfectly plausible, I would proffer another suggestion by no means mutually exclusive.

I suppose the question I would ask is whether the dust is an even layer (which, if static alone was the reason, one would expect to happen), or whether dust preferentially settled on certain areas of the fan.

One thing that would occur to me would be an analogy to the way rivers drop sediment around a bend?
 

Offline neilep

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Re: Why and How is there dust on Fan Blades ?
« Reply #4 on: 02/01/2006 16:43:09 »
oooh !!...the dust has in fact settled on a certain areas of the fan...albeit the same distribution on each blade ie: it is NOT an even layer.

Men are the same as women.... just inside out !!
« Last Edit: 02/01/2006 16:43:49 by neilep »
 

Offline DoctorBeaver

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Re: Why and How is there dust on Fan Blades ?
« Reply #5 on: 02/01/2006 17:28:41 »
Fans suck air from behind. Any dust in the air will be drawn across the blades and static seems an extremely plausible answer for why it sticks there
 

Offline ukmicky

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Re: Why and How is there dust on Fan Blades ?
« Reply #6 on: 02/01/2006 17:53:42 »
quote:
oooh !!...the dust has in fact settled on a certain areas of the fan...albeit the same distribution on each blade ie: it is NOT an even layer.


Neil its dust sticking to moisture

Moisture in the air would settle on the blades in the same quantities and places on each blade but the covering of moisture wouldn't be uniform over the entire blade as the forces near the centre are different to those at the edge
Michael


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« Last Edit: 02/01/2006 18:16:29 by ukmicky »
 

Offline neilep

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Re: Why and How is there dust on Fan Blades ?
« Reply #7 on: 02/01/2006 18:18:45 »
Thanks all....can you tell me why the dust is just on the front of the blades ?

Men are the same as women.... just inside out !!
 

Offline ukmicky

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Re: Why and How is there dust on Fan Blades ?
« Reply #8 on: 02/01/2006 18:50:27 »
Neil if Im right and its due to moisture

Then the answer to the second question could be that an effect of the fan blades moving  air would cause the front and back of the blades to be at different temperatures due to air friction .
The side doing the work would be hotter, allowing moisture to condense on one side and maybe not the other.

There would also be an air pressure difference between the front and back



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« Last Edit: 02/01/2006 19:01:24 by ukmicky »
 

Offline DoctorBeaver

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Re: Why and How is there dust on Fan Blades ?
« Reply #9 on: 02/01/2006 19:42:13 »
Due to the shape of the blades, you'll probably find that the pressure on the backs of them is lower than on the front
« Last Edit: 02/01/2006 23:20:26 by DoctorBeaver »
 

another_someone

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Re: Why and How is there dust on Fan Blades ?
« Reply #10 on: 03/01/2006 01:08:14 »
quote:
Originally posted by DoctorBeaver

Due to the shape of the blades, you'll probably find that the pressure on the backs of them is lower than on the front



I would have thought the converse is true.

In order to push the air forward, it needs to create lift on the back of the blade, which means that pressure should be less on the back.

It would also mean that air would be travelling slower over the front of the blades than over the back of the blades.
 

Offline DoctorBeaver

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Re: Why and How is there dust on Fan Blades ?
« Reply #11 on: 03/01/2006 03:01:45 »
quote:
   quote:Originally posted by DoctorBeaver

    Due to the shape of the blades, you'll probably find that the pressure on the backs of them is lower than on the front



I would have thought the converse is true.

In order to push the air forward, it needs to create lift on the back of the blade, which means that pressure should be less on the back


That appears to be exactly what I said
 

Offline neilep

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Re: Why and How is there dust on Fan Blades ?
« Reply #12 on: 03/01/2006 03:53:45 »
I thought so too. I didn't want to mention it because I know what it's like when you two start !! ;)

Men are the same as women.... just inside out !!
 

Offline ukmicky

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Re: Why and How is there dust on Fan Blades ?
« Reply #13 on: 03/01/2006 03:56:44 »
quote:
I thought so too. I didn't want to mention it because I know what it's like when you two start !!

Fight, Fight, Fight:D

Michael                 HAPPY NEW YEAR                    
« Last Edit: 03/01/2006 04:19:15 by ukmicky »
 

Offline neilep

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Re: Why and How is there dust on Fan Blades ?
« Reply #14 on: 03/01/2006 04:01:34 »
quote:
Originally posted by ukmicky

Fight, Fight, Fight:D

Michael                 HAPPY NEW YEAR                    





:DLOL !!!:D

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another_someone

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Re: Why and How is there dust on Fan Blades ?
« Reply #15 on: 03/01/2006 04:44:31 »
Mea Culpa apologies my brain was not in gear.
 

Offline DoctorBeaver

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Re: Why and How is there dust on Fan Blades ?
« Reply #16 on: 03/01/2006 11:53:52 »
Hakuna matata, rafiki wangu
 

Offline neilep

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Re: Why and How is there dust on Fan Blades ?
« Reply #17 on: 03/01/2006 16:08:36 »
Ahhhh !!....*sigh*...see ?...another_someone  IS human after all !! :)

Men are the same as women.... just inside out !!
 

another_someone

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Re: Why and How is there dust on Fan Blades ?
« Reply #18 on: 03/01/2006 16:39:10 »
quote:
Originally posted by neilep

Ahhhh !!....*sigh*...see ?...another_someone  IS human after all !! :)

Men are the same as women.... just inside out !!



But he can't speak Swahili he had to do quite a bit of hunting around for a translation. :)
 

Offline DoctorBeaver

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Re: Why and How is there dust on Fan Blades ?
« Reply #19 on: 03/01/2006 16:45:45 »
Siyo, mzee, nasema KiSwahili. Nimikaa na Uganda
« Last Edit: 03/01/2006 16:47:18 by DoctorBeaver »
 

Offline DoctorBeaver

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Re: Why and How is there dust on Fan Blades ?
« Reply #20 on: 03/01/2006 16:50:57 »
I've even written poetry in KiSwahili:-

Nitakaa hapa hata kifu changu,
Kwa sababu ni ndiko kwangu,
Kile siku nitaisifu myungu.
Wanipa uwezo wangu.

Good, ain't it! :D
 

Offline neilep

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Re: Why and How is there dust on Fan Blades ?
« Reply #21 on: 03/01/2006 17:40:02 »
I haveo no ideao whato you meano !!



HA...try and understand that then ?

Actually...a tranlation would be nice of your poem !!

Men are the same as women.... just inside out !!
 

Offline DoctorBeaver

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Re: Why and How is there dust on Fan Blades ?
« Reply #22 on: 03/01/2006 17:43:22 »
Translation:-

I will stay here all my life,
For this is indeed my home,
Every day I will praise the gods,
They give me my strength
 

Offline neilep

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Re: Why and How is there dust on Fan Blades ?
« Reply #23 on: 03/01/2006 17:46:23 »
Very Nice Eth !.....I like it.

Men are the same as women.... just inside out !!
 

Offline DoctorBeaver

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Re: Why and How is there dust on Fan Blades ?
« Reply #24 on: 03/01/2006 17:48:44 »
Thank you, dear boy
 

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Re: Why and How is there dust on Fan Blades ?
« Reply #24 on: 03/01/2006 17:48:44 »

 

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