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Anonymous Poster

Fluid Mechanics Question

07/22/2008 9:46 PM

I recently started thinking about boundary layer thickness and drag coefficients in compressible flow regimes and wondered whether there is/would be an advantage to developing a cost effective system to control the thickness of the boundary layer (ie: to reduce/control drag) thereby improving fuel efficiency?
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vicini
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Join Date: Dec 2007
Posts: 588
Good Answers: 13
#1

Re: Fluid Mechanics Question

07/23/2008 12:22 PM

look at golf ball.
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Jaguar
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Join Date: Jun 2007
Location: Florida
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#2

Re: Fluid Mechanics Question

07/24/2008 2:08 PM

Auto manufacturers do that all the time when they develop a new car body design. The best idea so far is drill thousands of tiny holes in the surface and connect them to a vacuum plenum on the underside. This reduces the boundary layer and promotes laminar flow. Keeping the holes cleaned out is the problem.

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U V
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#3

Re: Fluid Mechanics Question

07/24/2008 2:19 PM

You might also try pushing air out the holes to make a thicker slicker boundary layer.

Brad

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Gannet
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Join Date: Mar 2008
Location: Baltimore, MD
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Good Answers: 5
#4

Re: Fluid Mechanics Question

07/24/2008 7:58 PM

It has been estimated by NASA that as much as 50% of the fuel burn by civil aircraft is required to overcome viscous drag. Because there are alot more aircraft flying then new ones being built, I would recommend you consider development of retrofitable drag reduction technologies.
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Anonymous Poster
#5

Re: Fluid Mechanics Question

07/25/2008 8:36 AM

Thanks posters. The ideas suggested were some of the ones I was thinking of. Does anyone know of active research currently going on by automotive companies?
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