Aerodynamics in F1

Here are our CFD links and discussions about aerodynamics, suspension, driver safety and tyres. Please stick to F1 on this forum.
C Plinius Secundus
C Plinius Secundus
7
Joined: 05 Feb 2012, 21:06

Re: Ferrari F14T

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bhall wrote:The only potential area of concern I see with the sidepods is their height relative to others and how that contributes to the car's frontal area. It may not seem like much, but even small differences in frontal area can have a real effect on drag. Removing frontal area is a bit like engaging DRS.

http://i.imgur.com/f0ZLeTO.jpg

http://i.imgur.com/ttc8K8N.jpg
The higher sidepods also elevate the center of mass of the car (although we don't know the car internal weight/mass distribution), and even a couple millimeters make a huge difference.

armyk
armyk
4
Joined: 09 Jun 2013, 10:27

Re: Ferrari F14T

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Fdrag =1/2*p*v^2*Cd*A
As you can see only Cd (drag coefficient) and A (area) is different for each car, others are same.
I believe they have reason to have higher sidepods for example cooling system or downforce, I do not know.
Main problem is still PU, not sure if thy can improve it that fast to compete with Merc.

shelly
shelly
136
Joined: 05 May 2009, 12:18

Re: Ferrari F14T

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armyk wrote:Fdrag =1/2*p*v^2*Cd*A
As you can see only Cd (drag coefficient) and A (area) is different for each car, others are same.
So it is only Cd*A that counts, not frontal area
twitter: @armchair_aero

Akodo
Akodo
1
Joined: 12 Mar 2014, 09:22

Re: Ferrari F14T

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shelly wrote:
armyk wrote:Fdrag =1/2*p*v^2*Cd*A
As you can see only Cd (drag coefficient) and A (area) is different for each car, others are same.
So it is only Cd*A that counts, not frontal area
A in that equation for vehicles is the projected frontal area. We use different A's to suit the object being analyzed. For example, an aircraft wing uses the planform area. A reduction in frontal area is directly proportional to a reduction in drag.

shelly
shelly
136
Joined: 05 May 2009, 12:18

Re: Ferrari F14T

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Akodo wrote:
shelly wrote:
armyk wrote:Fdrag =1/2*p*v^2*Cd*A
As you can see only Cd (drag coefficient) and A (area) is different for each car, others are same.
So it is only Cd*A that counts, not frontal area
A in that equation for vehicles is the projected frontal area. We use different A's to suit the object being analyzed. For example, an aircraft wing uses the planform area. A reduction in frontal area is directly proportional to a reduction in drag.
Fdrag =1/2*p*v^2*Cd*A just tells you that if you build a 60% scale model of the car, drag on it will be 36% the full car (overlooking reynolds effects and so on).
It does not tell you anything about having a taller or shorter sidepod, because you cannot change A without changing Cd when you change the shape keeping the scale.

@mods. sorry for the offtopic, this chain of posts belongs elsewhere
twitter: @armchair_aero

bhall
bhall
244
Joined: 28 Feb 2006, 21:26

Re: Ferrari F14T

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Ain't nothin' wrong with a little off-topic science. At least, not to me.

For a body with a frontal area of, say, 1.2m^2 and a Cd of 0.75, figures roughly representative of contemporary F1 cars, that's traveling at 200kph (55.6 m/s) through air with a density of 1.225kg/m^3, drag force acting against it is 1704N.

If we reduce frontal area to 1.1m^2, but lengthen the body such that additional skin friction means we somehow retain a Cd of 0.75, drag force becomes 1562N.

By and large, that's the effect of frontal area on drag, though determining its exact effect on a Formula One car is probably a bit more involved due to the various shapes on them, and one would hope any real-world reduction of frontal area would carry with it a reduced drag coefficient anyway.

flyboy2160
flyboy2160
84
Joined: 25 Apr 2011, 17:05

Re: Aerodynamics in F1

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Bumped for merged posts.

monsi
monsi
10
Joined: 30 Mar 2013, 18:07

Re: Aerodynamics in F1

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http://www.bbc.co.uk/news/science-environment-27375349

Interesting article on football design. The description of the effects of roughness (from seams etc.) on flight distance interested me - "This agitation is essential for fast and reliable flight. A perfectly smooth ball experiences large amounts of drag and high aerodynamic forces."

Left me wondering why we see shiny smooth F1 cars ....

Lycoming
Lycoming
106
Joined: 25 Aug 2011, 22:58

Re: Aerodynamics in F1

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monsi wrote:Left me wondering why we see shiny smooth F1 cars ....
How about because the reynolds numbers involved are rather different?

Although with that said, the article is very nonspecific about a lot of the things they talk about, presumably to make it more accessible to a wider audience. I kind of understand what they're saying, but only by trying to connect their explanation of the effects with my knowledge of the mechanisms.

Tommy Cookers
Tommy Cookers
621
Joined: 17 Feb 2012, 16:55

Re: Aerodynamics in F1

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monsi wrote: ..... football design. The description of the effects of roughness (from seams etc.) on flight distance interested me - "This agitation is essential for fast and reliable flight. A perfectly smooth ball experiences large amounts of drag and high aerodynamic forces." ....
a bluff body eg a ball experiences up to 5 different types of flow according to Reynolds No (speed for a given ball/fluid combination)
these flow types are characterised by very different drag coefficients
at a critical Re adding roughness can change the flow from a high Cd type to a lower Cd type
ie at some speeds a smooth ball will have the same or less drag than a rough ball
at some other speeds the rough ball will have less drag
http://www.grc.nasa.gov/WWW/k-12/airpla ... phere.html

(and a spinning ball will generate eg lift, this is a whole other ball game)

when cars had wooden-spoked wheels roughening the spokes would at race speeds have actually reduced drag
or increasing spoke diameter (so raising Re beyond the critical value) would have also worked
but the above science was not then known
there's very few situations with road vehicles where this method is applicable, eg (note to self) none on bicycles