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Old 08-18-2014, 06:51 PM   #43 (permalink)
chillsworld
I got ideas
 
Join Date: Aug 2014
Location: Georgia, United States
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Beast - '97 Mercury Mountaineer
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Quote:
Originally Posted by aerohead View Post
If you look directly above the front wheel,near where the windshield edge would be,you'll barely make out a slot which is oriented with the color dye solution.
I believe that there are corresponding slots below as well.
Morelli divided the cooling air coming out of the engine bay into 4-different streams and experimented with duct size and geometry such that the air escaping out these slots blended perfectly with the surrounding flow field.
An isobaric/velocity contour map was created by pressure tap and velocity pressure measurements (you see this today in color CFD mapping),and working with Bernouli's Theorem,arrived at duct sizes which provide the air volume at a matched velocity,given the pressure environment its flowing into.
This cannot be modeled analytically yet and must be done by trial and error in the tunnel.(very expensive!)
If you get it wrong:
*air can flow into the exits
*jets can be formed which trigger shear-induced vorticity,eddies,turbulence
*Transverse-vectored jets can contaminate the boundary layer,trigger separation,along with the formation of form additional vorticity.
My opinion is that 'nailing' this sort of thing is completely outside the scope of what individuals can pull off without major money.
*air can stall within the duct

Did he "tune" the vehicles aerodynamics to a particular speed or range of speeds? I've been reading about ducting inlet/outlet size and it's impact on matching exhaust of the duct to external air speeds... So far everything I have read about it says that you would only be matching in certain situations. For example, when I posted earlier from the thread about designing duct work, it pertained to the student race cars that don't see high speeds. The consensus with them, was that exit speeds didn't matter because they didn't obtain speeds where a difference is air speeds would be noticed. I'm on my phone right now, I'll try to post something more substantial tomorrow from my computer.... But I was just wondering if you knew off the top of your head? I mean that would be a lot of variables that would need to work perfect to even match a single speed, much less all speeds??

-C
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I'm really beginning to like eco-humor
Quote:
Originally Posted by aerohead
PS you could add hamsters inside for a 'bio-hybrid' drive.
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