Tiger
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Registered: 12th Jun 01
Location: Leicestershire Drives:Astra VXR
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That snowplow one was mental! I couldnt believe how fast it hit the car!!
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gavin18787
Premium Member
Registered: 22nd Feb 05
Location: Basildon, Essex
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Interesting
Wonder if Ross Brawn was watching.......
Drives supercharged Tec with torque  
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SVM 286
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Registered: 13th Feb 05
Location: pain
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quote:
Originally posted by andy1868
my boss was telling me about it, they made a car covered in dimples like a golf ball and the MPG increased as it goes through the air cleaner apparently
*Rushes outside with centre punch and tapping stick*
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SVM 286
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Registered: 13th Feb 05
Location: pain
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quote:
Originally posted by Tiger
Even the mythbusters thought so and were amazed to be proven wrong!
Perhaps it's to do with some kind of small scale, yet beneficial surface turbulence.
I may be utterly wrong but I presume that the dirt/bumps set/s up dozens of (or more) tiny vortices on the surface of the car's body which 'lubricate' the passing air so to speak (a bit like a golf ball).
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SVM 286
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Registered: 13th Feb 05
Location: pain
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quote:
Originally posted by lostboy
quote:
Originally posted by Tiger
quote:
Originally posted by Ian
Cars aren't because it would be less safe for pedestrians and also more expensive to produce compared to the savings.
And surely, if they had a press to shape the body parts anyway, then they could have the press with dimples in it and that would be it?
I'd imagine that's just so it looks better, a dimply car would look wrong.
Imagine getting the dirt out of all those dimples too. 
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SVM 286
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Registered: 13th Feb 05
Location: pain
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quote:
Originally posted by Daveskater
Mythbusters ftw
They did find out that when the car was dirty it used more fuel though. Dirty and dimpled aren't the same.
Ah, bugger I thought that had explained why my RS is so fast, especially as it's always bloody filthy.
Was going to say, right, that's it, i'm never washing the car again. Cock it. 
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Tiger
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Registered: 12th Jun 01
Location: Leicestershire Drives:Astra VXR
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They were big dimples though, like the kind the a bowling ball would have made numerous times.
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ed
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Registered: 10th Sep 03
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It's the same reason why you shouldn't have the ports in your head polished to a mirror finish.
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SVM 286
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Registered: 13th Feb 05
Location: pain
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quote:
Originally posted by Tiger
They were big dimples though, like the kind the a bowling ball would have made numerous times.
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John
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Registered: 30th Jun 03
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They both explained and showed graphically in a wind tunnel how and why it works.
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Daveskater
Premium Member
Registered: 29th Apr 08
Location: Oxford, UK Drives: Jap wagon
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quote:
Originally posted by Tiger
They were big dimples though, like the kind the a bowling ball would have made numerous times.
Yup, they made them with tennis balls  That's what it looked like they were doing anyway
Numberwang!
Originally posted by AlunJ
I like you Dave, you are a man of men
Originally Whatapp'd by Neo
Dave's maybe capable of a drive-by cuddle
Look at my pictures
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John
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Registered: 30th Jun 03
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It was a bowling ball they used iirc.
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Daveskater
Premium Member
Registered: 29th Apr 08
Location: Oxford, UK Drives: Jap wagon
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They used this:
See here: http://www.autoblog.com/2009/10/22/mythbusters-golf-ball-like-dimpling-mpg/
Numberwang!
Originally posted by AlunJ
I like you Dave, you are a man of men
Originally Whatapp'd by Neo
Dave's maybe capable of a drive-by cuddle
Look at my pictures
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John
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Registered: 30th Jun 03
User status: Offline
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That's right, they cut the stuff out didn't they instead of making imprints.
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whitter45
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Registered: 15th Nov 02
Location: Norton
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quote:
Originally posted by Tiger
But, like they said though, why arent cars and aeroplanes designed in this way?
for aircraft providing dimples on leading edges has proved slightly successful - however the boundary layer eventually degrades inducing drag and causing less lift
The golf ball has dimbles as the dimbles induces drag behind the ball as it travels through the air thus forcing the ball through the air like a vortex style
Did Aerospace at Uni and covered all this
Basically at this level of dynamics dimbles do not provide the gain required for aerodynemic lift and the boundary layer is sacrificed
next generation is ground force for aircraft - same principle applied to F1 and indycar aerodynamics - did this for my dissertation
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1_Litre_Porsche_Beater
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Registered: 9th Apr 02
Location: Kent
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Could this explain why women with a bit of celly/dimples can generally bounce better than others? Same principle eh.....
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Ojc
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Registered: 14th Nov 00
Location: Reading: Drives : Clio 197
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quote:
Originally posted by 1_Litre_Porsche_Beater
Could this explain why women with a bit of celly/dimples can generally bounce better than others? Same principle eh.....
Ooohhh bbaaabbbyyy
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SetH
Member
Registered: 15th Jul 01
User status: Online
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quote:
Originally posted by 1_Litre_Porsche_Beater
Could this explain why women with a bit of celly/dimples can generally bounce better than others? Same principle eh.....
LMFAOAK47 you shall be commander of my HEFFER armies
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RichR
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Registered: 17th Oct 01
Location: Waterhouses, Staffordshire
User status: Offline
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the rougness factor helps to trap a boundary layer of air around the flow perimeter of the car; this boundary layer is actually more efficiently smooth than an polished surface. This is one of the reasons that most aeroplane wings are unpainted
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RichR
Premium Member
Registered: 17th Oct 01
Location: Waterhouses, Staffordshire
User status: Offline
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quote:
Originally posted by whitter45
quote:
Originally posted by Tiger
But, like they said though, why arent cars and aeroplanes designed in this way?
for aircraft providing dimples on leading edges has proved slightly successful - however the boundary layer eventually degrades inducing drag and causing less lift
The golf ball has dimbles as the dimbles induces drag behind the ball as it travels through the air thus forcing the ball through the air like a vortex style
Did Aerospace at Uni and covered all this
Basically at this level of dynamics dimbles do not provide the gain required for aerodynemic lift and the boundary layer is sacrificed
next generation is ground force for aircraft - same principle applied to F1 and indycar aerodynamics - did this for my dissertation
Did you study Wing in Ground effect vehicles, such as the Caspian Sea Monster; it was a phenommonal (sp) piece of engineering!
I'm currently looking at SWATH boats (Small Waterplane Area Twin Hull) which uses similar ground effect lift meaning the boat effectively needs less boat to float
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whitter45
Member
Registered: 15th Nov 02
Location: Norton
User status: Offline
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quote:
Originally posted by LiVe LeE
quote:
Originally posted by whitter45
quote:
Originally posted by Tiger
But, like they said though, why arent cars and aeroplanes designed in this way?
for aircraft providing dimples on leading edges has proved slightly successful - however the boundary layer eventually degrades inducing drag and causing less lift
The golf ball has dimbles as the dimbles induces drag behind the ball as it travels through the air thus forcing the ball through the air like a vortex style
Did Aerospace at Uni and covered all this
Basically at this level of dynamics dimbles do not provide the gain required for aerodynemic lift and the boundary layer is sacrificed
next generation is ground force for aircraft - same principle applied to F1 and indycar aerodynamics - did this for my dissertation
Did you study Wing in Ground effect vehicles, such as the Caspian Sea Monster; it was a phenommonal (sp) piece of engineering!
I'm currently looking at SWATH boats (Small Waterplane Area Twin Hull) which uses similar ground effect lift meaning the boat effectively needs less boat to float
no mate most of my ground effect work was on indy cars for the US
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