Quote:
Originally Posted by winkosmosis
What do you mean "no low drag car has a simple inclined windshield"? The Prius has a 20 degree windshield.
Or are you talking about flat vs curved? No one has even mentioned flat windshields.
The more sloped windshield doesn't increase drag.... Those supercars have shallow windshields just like the Prius, because they reduce drag. They aren't building their cars with anti-aero principles. They're designing them to be as aerodynamic as possible, with as little lift as possible, or even downforce. And designing for downforce doesn't mean you suddenly don't care about reducing drag.
Indycars and F1 cars have high coefficients of drag because of their downforce surfaces, but the other surfaces are as aerodynamic as possible. An airplane has a low coefficient of drag when the wings are parallel to airflow, but in the real world they generate lift by flying at an angle, which means their drag is pretty high. Yet airplanes generally have fuselages designed to be as aerodynamic as possible.
By pressurized air I mean air that is at higher pressure than the surrounding atmosphere.
Edit: The article specifically states that you can reduce drag by adding arch and frontal area. This is common sense, like I said in the other thread. If you decrease Cd by 10% and frontal area only goes up by 5%, voila you decreased drag.
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*None of those cars are low drag*
*Indycar bodies are Cd 0.25
*Indycar bodies with wheels are Cd 0.54
*Indycar bodies with wheels and wings are Cd 1.27
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* The fuselages which I studied to create the 'Template' are Cd 0.066
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* Once air begins to move,it cannot be at a higher pressure than the undisturbed air mass around it.
* Air,by definition cannot actually strike the vehicle.Air immediately adjacent to the body boundary is in a zero-slip situation.Air beyond the actual surface will be the turbulent boundary layer.The 'ideal'/'inviscid' outer flow can strike this.
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Hucho recommends against adding frontal area,however in your example you are correct.A car of Cd 0.30 and frontal area of 22 ft-sq,if modified as in your example would see a 2.75% increase in mpg at 55-mph.