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Old 07-26-2009, 06:52 PM   #5 (permalink)
Frank Lee
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Blue - '93 Ford Tempo
Last 3: 27.29 mpg (US)

F150 - '94 Ford F150 XLT 4x4
90 day: 18.5 mpg (US)

Sport Coupe - '92 Ford Tempo GL
Last 3: 69.62 mpg (US)

ShWing! - '82 honda gold wing Interstate
90 day: 33.65 mpg (US)

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Quote:
Originally Posted by Deezler View Post
Rounded whenever possible! But your area of flow detachment would probably be pretty small even with a sharp edge. Remember that your boundary layer has some thickness to it, and can cushion these edges.
By that point on the car the flow isn't really laminar anyway, right? That boundary layer gets bigger and fatter as it moves on back.

Remember this car?



Of the three PNGVs, it had the 2nd best Cd. Looks to me like the backlight was designed so that flow would reattach at the "trunk lid". So if the geometry downstream supports it, seems to me that transition isn't as critical as we'd like to think.
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