Aerocivic - how to drop your Cd from 0.31 to 0.17

[Coyote X]

After you swap out to LED park lights if you want to reduce the headlight load you can wire up some relays to switch them to series load instead of parallel. That will make them dimmer but not really dark. It will cut the load in half though

The other thing would be using some relays to switch them out you can add several silicon diodes in line. You get a .7V drop across a diode so add 5 of them in series will drop you 3.5V. Just make sure to pick big enough diodes to handle the load.

[MetroMPG]

I've heard of an instance where a university team solar car was forced off the road due to rubbernecking. Ended up catching a culvert and flipping the solar car. Fortunately nobody was hurt.

EDIT: the comparison of your Civic to a solar car (in terms of aero optimization) isn't that much of a stretch either either.

[Peakster]

Whatever happened to your additional 'wind screen' :

[SVOboy]

Rain?

[Peakster]

Originally Posted by SVOboy

Rain?

Mmm. I don't think so. Not according to this previous post by basjoos:

The second windshield added about 4mph to my terminal velocity on the "calibrated" downhills on my drive. I drove through some light rain and didn't even notice it on the vinyl other than the occasional drop running back along the vinyl. Most of th rain (and bugs) follows the smooth airflow over the vehicle. And best of all, no evidence of the "A" pillar vortex based on the behavior of the water droplets on the front side windows.

[basjoos]

Coyote X, good idea about using series connecting the headlights and also using doides to customize the voltage drop.

The aero benefits of the "second windshield" (by eliminating the "A" pillar vortex and smoothing the airflow over the front of the car) were undeniable, but I had some operational problems with it when operating in cold rainy weather. I'm in the process of replacing the clear vinyl on the "windscreen" with Lexan. The vinyl was clear enough when looked at straight through (90 degrees), but was hazy when viewed through at an angle (30 degrees) as it is near the bottom of the windscreen. It also had a tendancy to overwealm the Fog-X and fog up on the inner surface when driving in cold, wet conditions. The Lexan should take care of the low angle visibility problem and I need to get a good watertight seal along the front and sides of the "windshield" so water can't find its way onto the hot hood and end up condensing on the cold inner surfaces of the "windshield". Also considering adding a windshield wiper to the "windshield" to placate any cops that might freak out at a car driving in the rain without wipers, even if I don't really need them.

[newtonsfirstlaw]

Basjoos, you might want to stick a sock full of crystalline kitty litter (it's silica gel, the cheapest source you can find) somewhere in that space to get rid of any lingering moisture that finds its way in there.

[free-electron]

I read this and was so impressed I had to write about it on my blog.

You can read my thoughts at http://www.energyrefuge.com/blog/caf...-be-that-hard/

[Darxus]

Nice.

I was recently thinking about wheel spoilers and I thought of something I think is relevant.

Your front wheel spoiler mostly pushes air down, where it will end up hitting the tire (or ground) still anyway. I believe that won't help you any, and that it would be more efficient to just push the air directly to both sides of the wheel. Possibly more to the outside of the car than under the car due to the rest of your aerodynamics. So you would have a wedge where the leading edge is a vertical line.

And I would expect you to benefit from putting another set of spoilers behind the rear wheels (working well with your dual layer side skirts).

Of course I have no idea if these would give you enough benefit to be worth you doing.

[MetroMPG]

Originally Posted by Darxus

And I would expect you to benefit from putting another set of spoilers behind the rear wheels (working well with your dual layer side skirts).

That's a good observation for behind the rear tires. But do you mean to add a "boat tail" rather than "spoiler"?

You'll see wheels/tires effectively boat tailed on this car:
http://www.design-classic-cars.de/auto-union/stuck1.jpg