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Old 06-05-2012, 10:13 AM   #19 (permalink)
NeilBlanchard
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The air flow is probably going to be a combination of the to flow diagrams that George posted. If you know that an ideal vehicle has air flow that is first accelerated outward in all directions by the front of the vehicle, and then smoothly closes back into place after the vehicle has moved past. To achieve this, the air pressure must be as even as possible all over the vehicle.

If there are areas of low(er) pressure, then they will pull the air away from the higher pressure areas. The largest areas of low pressure on this vehicle will be behind the truncated front fenders. Some air will flow through the front grill, through the engine bay and past the spinning front wheels (I am assuming) and then will exit into this area, and will partially "fill in" this zone, but this exhaust air flow itself will be turbulent, and may not form a trapped pocket, similar to the bed of a pickup for example.

The result will be, I think, that there will be both a lot of turbulence and a lot of air will be pulled down from the hood and lower windshield, as well. Maybe this turbulent area will allow the air flowing off the fender to "bridge" to a point on the rear of the vehicle and reattach? The only way to "know" is to tuft test it.

Here's a vehicle called the Trev that addressed this issue by having a really "fat" door, hinged at the back:




Trev (two-seater renewable energy vehicle)
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Ideally, the sides would be slightly convex; not slightly concave.
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