|
||||||||||
|
||||||||||
12 Feb 2003, 19:44 (Ref:504763) | #1 | ||
Veteran
Join Date: Oct 2002
Posts: 1,618
|
Frontal Area
how would one go about computing the frontal area of something such as a racecar?
and I mean this in the realistic rather than the theoretical sense |
||
__________________
I refuse to let fact get in the way of my opinion |
13 Feb 2003, 03:06 (Ref:505110) | #2 | ||
Veteran
Join Date: Dec 2002
Posts: 706
|
I would presume it would be a matter of getting out your tape measure, taking some measurements and working out the area in square centimetres (or inches).
|
||
__________________
"If a man could be crossed with a cat, it would improve the man but deteriorate the cat." Mark Twain |
13 Feb 2003, 04:57 (Ref:505147) | #3 | ||
Veteran
Join Date: Oct 2002
Posts: 1,618
|
wow i feel stupid i should have specified about when u have curves and the like...for example an F1 car is it still the same just a head on view?
|
||
__________________
I refuse to let fact get in the way of my opinion |
13 Feb 2003, 06:17 (Ref:505164) | #4 | ||
Veteran
Join Date: Dec 2002
Posts: 706
|
as far as I know it is just the same as a head on view - the total displacement does not vary whether you are pushing a flat or a tapered surface, the air has to find a way around regardless (eg I and < have the same frontal area).
The coefficient of drag measures the "efficiency" (not quite the right term?) or the air passing around the object - obviously for this measure a flat surface ( I )will be outperformed by a tapered one( < ) (wish I had a white board - but I think this makes sense ) |
||
__________________
"If a man could be crossed with a cat, it would improve the man but deteriorate the cat." Mark Twain |
13 Feb 2003, 10:15 (Ref:505279) | #5 | ||
Veteran
Join Date: Dec 2001
Posts: 6,359
|
Frontal area is just as you see it in a head on view of the vehicle. The effect of the shape as seen in three dimensions is taken cars of by the drag coefficient (Cd).
|
||
__________________
Doing an important job doesn't make you an important person. |
14 Feb 2003, 03:33 (Ref:506080) | #6 | |||
Veteran
Join Date: Dec 2002
Posts: 706
|
Quote:
|
|||
__________________
"If a man could be crossed with a cat, it would improve the man but deteriorate the cat." Mark Twain |
14 Feb 2003, 12:28 (Ref:506405) | #7 | |
Veteran
Join Date: Jun 2001
Posts: 1,831
|
Don't forget that frontal are is also effected by overall rake angle and wing settings.
|
|
|
14 Feb 2003, 12:45 (Ref:506428) | #8 | ||
Team Crouton
20KPINAL
Join Date: Oct 2001
Posts: 39,947
|
Does assessment of frontal area work in the same way for human beings?
Sorry for being ever-so-slightly smutty, must be coz of Valentines Day..... ) |
||
__________________
280 days...... |
14 Feb 2003, 13:33 (Ref:506479) | #9 | ||
Veteran
Join Date: Jul 2002
Posts: 1,332
|
MMike, you're clearly qualified to talk about this, glad to see you here. Perhaps you can set me straight, I thought that frontal area was independant of the plane of attack for the wings, shape of the body, etc, and the Cd reflects those things... much as GTV27 and Dave Brand explained above... Am I not understanding something correctly?
|
||
__________________
Juliette Bravo! Juliette Bravo!!!! |
14 Feb 2003, 16:57 (Ref:506657) | #10 | ||
Veteran
Join Date: Oct 2002
Posts: 1,618
|
see this is what i was told to some extent al though not explained this well and i got confused, what is the formula or whoever it is determined?"
Last edited by avsfan733; 14 Feb 2003 at 17:01. |
||
__________________
I refuse to let fact get in the way of my opinion |
14 Feb 2003, 16:58 (Ref:506658) | #11 | ||
Veteran
Join Date: Oct 2002
Posts: 1,618
|
see this is what i was told to some extent al though not explained this well and i got confused, what is the formula or whoever it is determined?
|
||
__________________
I refuse to let fact get in the way of my opinion |
14 Feb 2003, 17:48 (Ref:506725) | #12 | |||
Veteran
Join Date: Dec 2001
Posts: 6,359
|
Quote:
|
|||
|
14 Feb 2003, 20:52 (Ref:506900) | #13 | ||
Veteran
Join Date: Jul 2002
Posts: 1,332
|
Oh, I get it now... MMike (and Dave, above) are talking about the fact that if you make a wing angle change, it will effect the frontal it presents slightly. I should think that for a front wing it won't matter much, because the whole car is still behind it, but the rear could probably make some significant changes...
|
||
__________________
Juliette Bravo! Juliette Bravo!!!! |
15 Feb 2003, 13:40 (Ref:507566) | #14 | |
Veteran
Join Date: Jun 2001
Posts: 1,831
|
Yes, certainly the difference is minimal if you take into account wing angles. But ultimately it will effect the numbers. Most simply use a close guesstimate and stick with it for all their calculations. For closed wheeled prototypes, 1.8-2.0 m^2 is a good ball park number. You'll be within 10% of the actual number and it won't effect your results much.
An example of the slight difference. These are real numbers for a GTP car, won't disclose the actual car: Frontal projection sans wing: 1.665 m^2 Add wing, very low wing architecture: 1.68 m^2 These numbers come from a CAD drawing, CAD number is very close to the real frontal projection as measured. Last edited by MulsanneMike; 15 Feb 2003 at 13:44. |
|
|
15 Feb 2003, 20:28 (Ref:507882) | #15 | ||
Veteran
Join Date: Jul 2002
Posts: 1,332
|
Excellent, thanks for the example MMike!
|
||
__________________
Juliette Bravo! Juliette Bravo!!!! |
25 Feb 2003, 16:46 (Ref:517312) | #16 | ||
Racer
Join Date: Feb 2003
Posts: 182
|
Wat is so importand about the actual frontal area. Is there a way to measure the frontal area from the car plus the turbulent area created by the boundarylayer.
|
||
|
26 Feb 2003, 20:01 (Ref:518603) | #17 | ||
Veteran
Join Date: Jul 2002
Posts: 1,994
|
I will say straight up that I have no idea if this will work but if you had time to put grid paper on a background place the car in front of it and using some form of light you could project the image of the car,trace around it and count the squares in the area.measure the angles of the front end and you should be pretty close in my opinion.
|
||
__________________
Succes is a result of judgment,that is inturn a result of experience that has come from instances of bad judgment. "Montoya made some last minute changes to his suspension but it seemed to effect it's handling"-Classic |
26 Feb 2003, 21:46 (Ref:518722) | #18 | |||
Veteran
Join Date: Dec 2001
Posts: 6,359
|
Quote:
Does that answer your question? |
|||
|
4 Mar 2003, 15:57 (Ref:524572) | #19 | ||
Racer
Join Date: Feb 2003
Posts: 182
|
Sometimes it's easyer to reduce your cd than reduce the frontal area. I think the frontal area of disturbed air around the car is more importand than the car's frontal area.
|
||
|
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
Aerodynamic drag coefficient and frontal area of a Honda Accord? | pitcrew | Racing Technology | 4 | 16 Mar 2005 23:54 |
Welcome Area | jpchenet | Sportscar & GT Racing | 17 | 2 Jun 2004 12:42 |
Holding area | graeme | Marshals Forum | 21 | 26 Jan 2004 12:26 |