Wake square feet to CD reduction conversion?

[Phase]

Is there a formula or chart or anything that shows how much of a CD reduction happens for every certain amount of square feet Increments of the wake is reduced?

Ignoring the rest of the car and it’s shape, for example, if your cars wake us 20 square feet, and you reduce it to 18 square feet or even 15 square feet, how much of the drag would be reduced?

[freebeard]

The word that comes to mind is 'nebulous'. The wake doesn't have a distinct boundary.

A graph could be produced by equiping a chase vehicle with a grid held forward of the CV with tell tail tufts.

[aerohead]

I'm two states from home on a family medical emergency, on a computer I can hardly navigate.
* Go to GOOGLE
* search for ' windsor body cfd model'
* scroll down to find ' MDPI, The Aerodynamic Effects of a 3D Streamlined Tail on the Windsor Body,' by PhD Jeff Howell et al., at Loughborough University.
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They've cfd'd and wind tunnel tested 2D and 3D tails.
* As with earlier presentations, the drag coefficient changes exactly as a function of the size of the wake.
* And the 3d tail is 57% more efficient at streamlining than the 2D tail.
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Since Jeff shows his references, we know that he's aware of the most complicated , compound- curvature tails of Jaray, Fachsenfeld, Kamm, and Mair,etc.,and when tumblehome and edge radii are introduced, there will be an additional 16.6% drag reduction for the 'ideal' shape.
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The guy who did the tail fabrication for research ( PhD Max Varney.
, has moved on to Mercedes-Benz' Formula One
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If they find someone to fabricate the compound-surface tail as with the 1922 and beyond reporting, we'll have drag curves for the 'template' elongations from both CFD and wind tunnel. As in the past, there's nothing which can exceed it's efficiency for drag reduction, if the vehicle's forebody and underside has already been optimized.
All future low-drag automobiles will have it.



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