Fuelly Forums - Perfect Base Car For Super Aero Car/EV?

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What about starting with an old mazda mx-3 ? The cars are very sleek ( looking ) and have a small frontal area.

( They are actually pretty high .Cd wise at .32. )

Can you imagine just taking an old piece of crap car and turning it into an 'art' car that looks like a fish ? ( Using spray foam on the outside of the body of the car, which would then be shaped )
Modify the car to look just like a boxfish or other slippery fish and don't worry at all about the car looking silly.
Go ahead and replicate the fishes' shape in every detail - the eye sockets, gills etc- even include the fin.
What you end up with is a car that would have a SUPER low .Cd, but with traffic stopping looks that would make even the most carefree driver cower in shame.

The solution : hit up an aquariam shop about advertising ... and get paid to drive your thing around .
No creative excuses needed for driving a 'fish' car.

Dignity intact. :)

I can, been pondering turning my minivan into a boxfish, well, sort of. I am looking at cloning the aero features of the DaimlerChrysler Mercedes Bionic concept that was inspired by the boxfish...
my thread... https://www.gassavers.org/showthread.php?t=6919

Quote:

Originally Posted by Mighty Mira (Post 19618)

Very good point. I think the key is to make the bottom as curved as the top, or at least, to angle the end upwards (slightly). I think the latter is the better solution, to be honest.

It makes sense if you realize that Bernoulli's explanation is not really the proper explanation for why lift is generated. See here. The reason lift is generated is that air sticks to the surface, and momentum is conserved. Hence whatever direction the air tends to go after it leaves the vehicle is opposite to the direction the vehicle will be propelled. And provided that the slope the air is attempting to stick to is not steeper than a certain grade, you can direct it in any direction you choose.

In fact, now that I know about it, teaching the Bernoulli effect as the primary cause for lift is really doing a disservice to aerodynamics understanding.
...

The essay referenced above does not properly address lift.

I do not have a text handy, do not remember the equations off the top of my head and could not reasonably represent them in ASCII even if I did.

However, as I recall, lift is produced both by pressure differential (which can be directly measured) and by downflow (which can be observed but is much harder to quantify). For a specific airfoil, the relative contribution of each is determined by the aspect ratio of the wing

So a short stubby wing like a typical rudder will primarily generate lift from downflow, but long skinny wings like the main wing on a high performance sailplane will primarily generate lift from the Bernoulli effect.

An infinite wing (meaning infinite span) has infinite lift and no downflow.

Modern jetliners and sailplanes typically have winglets on their wingtips. These are designed to improve the lift to drag ratio of the wing by reducing the wingtip vortices, which also reduces the downflow.

Considered as a wing, the typical autobody has a pretty low aspect ratio so you might suppose that downflow dominates. However automobiles generally do their flying close to the ground so you may want to research wing in ground effect (WIG) vehicles, instead of airplanes.

https://en.wikipedia.org/wiki/Wing_In_Ground_Effect

Quote:

Originally Posted by Nerds laugh at me (Post 96791)

What about starting with an old mazda mx-3 ? The cars are very sleek ( looking ) and have a small frontal area.

( They are actually pretty high .Cd wise at .32. )

That's what I was going to say! The GS model actually has a lower Cd, and if you put the RS model hatch garnish on it, it's even lower.
I believe mine is at about .27 with the side skirts, and underbody on (maybe less).
Here's a thread about an MX-3 electric conversion in progress:
https://www.mx-3.com/phpBB3/viewtopic...ric+conversion

Call me crazy, but I think the following two pictures should yield some ideas for the ultimate EV.

https://hd.sr5.com/blog/wp-content/up...009/07/rv1.jpg

https://members.optusnet.com.au/~dami...n/mainpic1.JPG

I know, I know, you're thinking "An RV and a 4X4, what is this guy thinking?"
:D

But follow me here . . . The RV has a GVWR of over 6000 lbs, but the chassis is still Toyota pickup. Ditch the camper top, engine, and related systems, and it should not be much heavier empty than a similarly converted Toyota pickup, weight mostly in the extra frame length . . . but still with a 6000 lb GVWR. Drop on a crew-cab cabin similar to the 4X4 picture, make a light body that gently slopes back to a boat-tail at the end aft of the rig, and fill it up to the 6000 lb GVWR with batteries. With extensive aero-modding on the rest, I imagine the top-speed/range/payload would be pretty darn impressive. Anyone want to do some calculations?