11-06-2013, 06:31 PM
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#21 (permalink)
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Master EcoModder
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void
Quote:
Originally Posted by redyaris
Patent attornies are definetly part of the BORGE Collective...
I will now go and read chapter 9, Commercial Vehicals; Aerodynamics of Road Vehicles, Volf-Heinrich Hucho, to see what I can learn about the void...
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Up at the Aero Forum,under the thread 'Full-Boat-Tail Trailer for T-100' you'll find some graphical drag tables derived from wind tunnel analysis which cover 'gap-drag.' Some of the tables I derived from composite tables Hucho published.You don't have to measure or calculate anything,just look and read Cd. There might be something of interest to you there.
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11-06-2013, 08:58 PM
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#22 (permalink)
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Cyborg ECU
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Quote:
Originally Posted by aerohead
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Well that explains to some extent the shape of the fairings behind the prius's rear wheels. I've long admired that detail of those cars.
-james
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See my car's mod & maintenance thread and my electric bicycle's thread for ongoing projects. I will rebuild Black and Green over decades as parts die, until it becomes a different car of roughly the same shape and color. My minimum fuel economy goal is 55 mpg while averaging posted speed limits. I generally top 60 mpg. See also my Honda manual transmission specs thread.
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11-08-2013, 05:20 PM
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#23 (permalink)
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Master EcoModder
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recent 'void' drag example
A recent example of drag degradation due to a 'void' would be the 2013 Bugatti Veyron 16.4 Grand Sport Vitesse.
When the roof panel is removed the top speed falls from 255 mph,to 233 mph.
A 22 mph drop.Or,a 9.44 % reduction in top speed due to the extra drag created by the void.
Using Wolf Heinrich Hucho's drag/top speed relationship loosely,this 9.44 % change in top speed would indicate an approximate 28.3 % drag increase. 
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11-08-2013, 10:53 PM
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#24 (permalink)
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Master EcoModder
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Quote:
Originally Posted by aerohead
A recent example of drag degradation due to a 'void' would be the 2013 Bugatti Veyron 16.4 Grand Sport Vitesse.
When the roof panel is removed the top speed falls from 255 mph,to 233 mph.
A 22 mph drop.Or,a 9.44 % reduction in top speed due to the extra drag created by the void.
Using Wolf Heinrich Hucho's drag/top speed relationship loosely,this 9.44 % change in top speed would indicate an approximate 28.3 % drag increase. |
Wow, and that's on a very high drag vehicle too! |
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02-14-2014, 06:10 PM
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#25 (permalink)
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Master EcoModder
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another canopy drag table
I read through 'THE LEADING EDGE' by Goro Tamai,and have adapted an expanded version of a canopy drag table he published.It's below the other images at top of page one.
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