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Old 06-10-2017, 04:25 PM   #1 (permalink)
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Too much or too little taper and rear slope, opinions?



Too much or too little taper and rear slope, opinions?
I am aiming for a CD of about 0.20 ultimately. The rear wheel is in the center (trike style design, not a four wheeler).

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Old 06-10-2017, 04:54 PM   #2 (permalink)
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taper

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Originally Posted by mikesheiman View Post


Too much or too little taper and rear slope, opinions?
I am aiming for a CD of about 0.20 ultimately. The rear wheel is in the center (trike style design, not a four wheeler).
For 3-dimensional flow,this 1981 VW 'Flow' body,by Buchheim et al. has the most extreme curvature which will still prevent separation.

Here's the same 'car' with some of the tail chopped away,with litt'e drag increase

Follow the contour as far as you're able,then just chop it off as with a loaf of bread.
You really want curves instead of angles.
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Old 06-10-2017, 05:30 PM   #3 (permalink)
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Originally Posted by aerohead View Post
Follow the contour as far as you're able,then just chop it off as with a loaf of bread.
You really want curves instead of angles.
Would the same thing (fat doors) work for a normal passenger car ?
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Old 06-10-2017, 05:45 PM   #4 (permalink)
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same thing?

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Would the same thing (fat doors) work for a normal passenger car ?
Please expand on your question a little.I'm not sure about your question.Thanks!
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Old 06-10-2017, 05:49 PM   #5 (permalink)
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Please expand on your question a little.I'm not sure about your question.Thanks!


Coreflute curved side panels added to the doors to a standard car.

That could easily* be done and it would give the same side profile as in the pictures. Doing the windows might be a challenge though but for the metal panels it might be doable.

I'm talking about the top picture.

My car already roughly matches the bottom picture.
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Old 06-10-2017, 05:56 PM   #6 (permalink)
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added to doors

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Originally Posted by ar5boosted View Post


Coreflute curved side panels added to the doors to a standard car.

That could easily* be done and it would give the same side profile as in the pictures. Doing the windows might be a challenge though but for the metal panels it might be doable.

I'm talking about the top picture.

My car already matches the bottom picture.
Okay,got what you're saying.
Hucho warns us not to do anything which would add frontal area.Then Don Burr trucking in England does is to a 18-wheeler trailer and still gets a drag reduction.
It's always better to 'remove' body,than add it,but you could do a quick and dirty mockup with cardboard and tape and see what happens.
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Old 06-11-2017, 01:52 PM   #7 (permalink)
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The curve should be smooth and continuous. That means the panels before and after the door[s] as well. The door cut line is thickened, the door swing may be compromised, ...

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