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Old 08-07-2020, 04:22 PM   #171 (permalink)
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Old 12-09-2021, 03:13 PM   #172 (permalink)
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HHR

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Originally Posted by HotRodEconomist View Post
Is the Chevy HHR on here?
I've watched for years and came with nothing. And without a drag-limited top speed, it's impossible to reverse-engineer.
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Old 12-09-2021, 03:19 PM   #173 (permalink)
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surprising

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Originally Posted by Focus-Ak View Post
"source book: The World of Automobiles, ..."

The Jaguar E, at Cd=0.44, is surprising. That model sure had my eyeballs fooled. It must be all that extra surface area.
It's another pseudo-Jaray 'fastback' with such a steep greenhouse rear slope that the air can't remain attached.
You'll notice that today's Jaguar's don't have a roofline that radical.
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Old 03-13-2022, 11:40 AM   #174 (permalink)
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https://www.motortrend.com/reviews/2...t-look-review/

just picked up a 2022 Hyundai Sonata hybrid and see the thing has a .24 Cd.

other places I see it's 56.9" tall 73.2" wide. I can't find a stat but I would guess the frontal area is about 24 sqft similar to an A8 or a 7 series. That puts the CdA at 5.76. It's rated higher on the highway than in the city which is abnormal for a hybrid but maybe aero has something to do with that.
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Old 03-13-2023, 11:31 AM   #175 (permalink)
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How to measure

When figuring the frontal area using width, is it the car width or total width including side mirrors? Is there any adjustment made to total hieght to account for a sloping roof?
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Old 03-13-2023, 12:09 PM   #176 (permalink)
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adjustment

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Originally Posted by Mcgiiver View Post
When figuring the frontal area using width, is it the car width or total width including side mirrors? Is there any adjustment made to total hieght to account for a sloping roof?
The overall height of the vehicle, and it's width ( without mirrors ) is used.
The actual 'shadow' is what's measured.
When CAR and DRIVER went to the A2 Wind Tunnel to do their 'Drag Queens' testing, they set up a camera at 200- feet or meters from the cars. And typically, a reference 'area' or ruler is captured within the footprint of the image.
It's scanned into software, where the area is reduced to a pixel count, compared to the reference area, or 'length' captured.
They used a package from SEIMENS.
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Old 03-13-2023, 12:23 PM   #177 (permalink)
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2022 Subaru BRZ

Frontal area actual shadow, not simply width times height. = 20.29 sq.ft including mirrors.
Height 51.6"
Width 69.9" not including mirrors.

cd= 0.29
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Old 03-13-2023, 12:40 PM   #178 (permalink)
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'simply'

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Originally Posted by Mcgiiver View Post
Frontal area actual shadow, not simply width times height. = 20.29 sq.ft including mirrors.
Height 51.6"
Width 69.9" not including mirrors.

cd= 0.29
If you draw a 'box' around the gross profile, all the areas that are not 'vehicle' must be subtracted from the gross area. And then the area of the mirrors must be added in for the 'total.
EXAMPLE : 2014 NISSAN LEAF:
W- 69.685-inches
H- 60.984-inches
Gross area = 29.5116 square-feet
Net area = 24.50-square-feet
Equivalent to 83.018% of gross area.
------------------------------------------------------------------------------------
Since carmakers aren't terrifically forthcoming with official frontal areas, we're forced to estimate, just to be able to do math.
If, at a later date, we get access to the actual data, we just adjust our values accordingly.
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Old 03-13-2023, 01:15 PM   #179 (permalink)
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[QUOTE=aerohead;681548]If you draw a 'box' around the gross profile, all the areas that are not 'vehicle' must be subtracted from the gross area. And then the area of the mirrors must be added in for the 'total.

That is exactly the method I used.
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Old 03-16-2023, 10:51 AM   #180 (permalink)
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'exactly'

[QUOTE=Mcgiiver;681550]
Quote:
Originally Posted by aerohead View Post
If you draw a 'box' around the gross profile, all the areas that are not 'vehicle' must be subtracted from the gross area. And then the area of the mirrors must be added in for the 'total.

That is exactly the method I used.
You're good to go! Have fun with it.

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