Interesting Aerodynamic Cars (Mike Vetter's ETV, also Avion)

[arcosine]

Originally Posted by NeilBlanchard

This one is the SIM-LEI with a Cd of 0.19. Notice the small mirrors with the supplemental video mirrors.

The tail look nice, the front looks like a plow. How is the air suppose to get around those fender protrusions. It needs more work to get the flow smoothed out on the body sides. The opening for the front wheels is too big. The bumps for the head lights are wrong, the flow is going out at an angle here, to get around the windshield.

[CFECO]

Perhaps the fender protrusions are to keep the air hitting the front of the car, to go over the car, and not interfere with the air going down the side of the car. Basically making it a 2-D shape in a wind tunnel. The sides are pretty smooth, the bulges are streamlined well and are the side guard door beams, they are on the outside to make the doors-car narrower. The headlights are..? Perhaps they create turbulence which washes over the mirrors, many cars now have headlights which are not smooth with the body, as in the photo. Our Toyota, different year but same style, has this flat place on the headlights which I am guessing, diverts the air around the mirrors. I was ready to take a grinder to it to smooth it out, but thought better....

[RedDevil]

It definitely IS meant to make the air flow over the roof rather than curl around the side. It enlarges the bulge of slow moving air ahead of the car, which now has the hood/windscreen as the easiest escape route, just wat we want.

Many new cars have protruding A pillars, making it look like the windscreen is sunken back.
This has the same effect, and as a bonus the A pillar can be made thicker and stronger without impairing view from the inside.
On the white car the A pillars protrude inwards, funnily enough. Apparently the plow nose has doen its work and they can now be smooth on the outside.

[Cd]

Originally Posted by RedDevil

Many new cars have protruding A pillars, making it look like the windscreen is sunken back.

When I did my tuft test ( 1993 Civic DX hatch ) I was surprised to find that the air did not run up the side of the rain channel on the sides of my windshield and instead just tripped over them as if they weren't even there. The windshield on this old of a car is not sunk in very much, but there is still quite a groove there that I would have thought would channel the air upwards.

[RedDevil]

The air will trip over it but still the air bubble ahead of the windscreen will be slightly bigger, creating a slightly more gentle flow (and slightly more upward).

To completely block that flow you'd need to make them protrude much further, but that might be a collision safety issue.

[NeilBlanchard]

The thing that jumps out at me on the SIM-LEI is the holey rims. It might be that they need to cooling for the in-wheel motors - there is one in each wheel; but somehow I doubt that is the reason for the wheels.

[CFECO]

If the wheels were made for airflow, I'd think they would look quite different.

[RedDevil]

They need to be as light as possible when there are motors in there, and they will not vent very well at the back because of that motor.

I cannot imagine they would put holes in there if it could be avoided. Look at the wheel spoilers ahead and behind the tires. These guys are not unaware of aerodynamics.

[freebeard]

The tail look nice, the front looks like a plow. How is the air suppose to get around those fender protrusions.

It's been covered but here's a car with 0.17 Cd:



It gets there with a low cowl line and a very gently curved A-pillar. Protruding A-pillars let snow build up on the windshield, at least on a '58 VW convertible's flat glass.

[Superfuelgero]

Originally Posted by Cd

When I did my tuft test ( 1993 Civic DX hatch ) I was surprised to find that the air did not run up the side of the rain channel on the sides of my windshield and instead just tripped over them as if they weren't even there. The windshield on this old of a car is not sunk in very much, but there is still quite a groove there that I would have thought would channel the air upwards.

If you take the trim off, it is fairly well sunk. It compares to most other newer cars, except the the set back continues to the header. I formed my own transitions/trim out of black silicone to get the effect i wanted.