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Originally Posted by Alastor187
The only similarity between a car and airfoil, as suggested in post 8, is that both have longer 'path' lengths along the upper surface.
My point was that this is not a criterion characteristic for developing lift, despite the fact the most common explanation of airfoils suggests the opposite.
A flat plate for example can create a significant amount of lift even though the top and bottoms surface path lengths are equal.
To digress even more off-topic, a car really isn’t shaped like a wing it is shaped like a car. Not to say the shape won’t create lift, but in my opinion it is often a misnomer to call it a wing just because it creates lift and has the airfoil similarity already mentioned.
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The similarities between a car and an aerofoil include a curved top surface and a large flat area underneath.
This is consistent with both the traditional explanation of lift (faster air = lower pressure) and the alternative lift mechanism described in your links (reaction of downward accelerating airstream).
A flat plate can creat lift, but in doing so it creates a large amount of turbulence. This leads to a large amount of drag and makes it a particularly inefficient device for creating lift (or downforce).
Design features used in the automotive world to reduce lift (and create downforce) include air dams to restrict airflow under the car, external aerofoils (upside down wings) and rear diffusers (which are again an upside down wing).