How much difference does aerodynamics make?
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From: Covington WA, USA
Originally Posted by i_heart_my_DB8,Feb 3 2006, 12:29 PM
Ok. So I'm wrong.
But in the examples I used: The Sprint car with the huge wing vs. the 360 Modena with the sculpted/flat underbody, is the same aerodynamic principle being utilized? I realize the end result is the same: at speed, differences in air pressure cause the car to be drawn to the center of the earth. But is there a differentiation between whether this is caused by increased air pressure from above vs. decreased air pressure from below?
But in the examples I used: The Sprint car with the huge wing vs. the 360 Modena with the sculpted/flat underbody, is the same aerodynamic principle being utilized? I realize the end result is the same: at speed, differences in air pressure cause the car to be drawn to the center of the earth. But is there a differentiation between whether this is caused by increased air pressure from above vs. decreased air pressure from below?
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From: Covington WA, USA
Originally Posted by Wisconsin S2k,Feb 3 2006, 12:31 PM
Cool. maybe you can help me get over my incredible fear of flying I have. 
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From: Tampa Florida
Originally Posted by NEODYMIUM,Feb 3 2006, 02:45 PM
The easiest way to get an idea of the drag FORCE is to take your car up to speed, for example 110 mph, let it decel maybe 5mph. Time your 5 mph decel and now you can find an average force.
D=m*("delta" V)/("delta t)
D=Drag force
m=car mass
"delta" V=change in velocity
"delta" t= Time to decel
Taking what mikegarrison stated we can calc. a rough drag coefficient
Cd=D/(1/2*rho*V^2*A)
Cd= Drag coefficient
The trick is to measure the frontal area of the car (the profile, not the actual surface area)
This is rough, but the decel experiment will at least let you compare cars for a given speed range.
D=m*("delta" V)/("delta t)
D=Drag force
m=car mass
"delta" V=change in velocity
"delta" t= Time to decel
Taking what mikegarrison stated we can calc. a rough drag coefficient
Cd=D/(1/2*rho*V^2*A)
Cd= Drag coefficient
The trick is to measure the frontal area of the car (the profile, not the actual surface area)
This is rough, but the decel experiment will at least let you compare cars for a given speed range.
The absolute best way is to go to a wind tunnel.
This link will help clear things up.
http://auto.howstuffworks.com/question497.htm enjoy!
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From: Tampa Florida
This is another link explaining how airplanes work and some of the principles of lift and drag apply to cars as well. A very good read.
http://travel.howstuffworks.com/airplane.htm
http://travel.howstuffworks.com/airplane.htm
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From: Jtown, Il
This would have to be done in neutral, correct? Otherwise the gearing of the car will strongly affect the "drag."
The absolute best way is to go to a wind tunnel.
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From: Tampa Florida
Originally Posted by NEODYMIUM,Feb 3 2006, 04:51 PM
yes
I know, but my wind tunnel is in the repair shop. I guess I could always just piss my girlfriend off when she's standing in front of my car though.
I know, but my wind tunnel is in the repair shop. I guess I could always just piss my girlfriend off when she's standing in front of my car though.
Hahahaha!!!!! Aint that the truth.
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From: Milwaukee Area
Originally Posted by mikegarrison,Feb 3 2006, 02:41 PM
Ah, well I'd like to. More people flying means more airplanes sold. But I haven't been able to get over my own fear of spiders, so maybe I'm not the best resource for that.
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