'There is no single best aerodynamic shape for.....'

[freebeard]

That’s all I have time for, for now. Say my name three times and maybe I’ll appear again in future.

An odd thing to say, does one need to be looking in a mirror to make it work?

What falls out of the assertion of oblique surfaces is that fineness ratio is your friend.

[JacobLeSann]

As much as I enjoy this site, I’ve learned far more about aerodynamics by testing vs posturing.

But it’s fun and thought-provoking to theorize back and forth with others.

I hope this divisive topic can lead people to a higher level of research/construction. Competition breeds innovation, I think.


P.S. where is the engine on the Template car? It looks like it’s kind of an afterthought.

[freebeard]

Thee Holy Template is so pure it doesn't need an engine.

Today I'm back to thinking about boat tialing my Baja.

[ConnClark]

I'm going to get Zen.

"The perfect shape is the one that isn't there."

[JacobLeSann]

Zen. I mean, that a good thought. You could use tuft testing and pressure measurement (better yet, a wind tunnel) to determine the perfect shape for modification of your car, which would normally be invisible. “The shape that isn’t there”

freebeard, would the rear wheels have pontoon fenders with spats? I think a beetle would be the perfect car to try and replicate a 30’s-40’s aerodynamic car. I think a long-tailed Bugatti Aerolithe could be very cool, for example. Split window at the rear? Could be very sweet. The beetle’s front windshield is very nice stock, but I bet you’d improve frunk space for sure. Lots of bodywork, though.

Biggest question for me is still: “how do you work on the engine?”


I find my 2006 Civic (most angled front end of any Honda I’ve seen) makes it a pain to work under the hood. My 90’s cars are like a godsend in comparison. I guess that’s my preference.

Still, conjecture, and off topic.

————————————————————————

Somewhat more on topic:

I think the idea of “apply these mods and you will get __ increase in MPG!” is an idea which is very misleading. I find this worse than the template, although they tend to go hand-in-hand. I don’t think anything about this is set in stone, beyond the idea of slowing the vehicle down. For example, I read so much on this site about “high RPM wastes fuel” yet I have a 120 MPG vehicle that sees life at 7500-9000 RPM. Hell, even on a bicycle I increased efficiency and saved my aching knees by shortening my crank arms and dropping down a gear while cruising. Those are less aerodynamic examples though.

Long story short, different strokes for different folks….er…vehicles.

[freebeard]

freebeard, would the rear wheels have pontoon fenders with spats?

Frunkless




Remember that Porsche I can't find that had a U-shaped step in the difusser I called entertaining? Like that.

The boat tail would truncated in a stainless steel deflector on the 4-into-1 exhaust header to form a Coanda nozzle, as below left.

[Grant-53]

To study fluid mechanics and boundary layers most books require a knowledge of differential equations. On my bicycle fairings I start with 5:1 aspect ratio and a Kamm reduction of 10-15% of length. I have done tuft testing and coast down tests under 20 mph. The template is a starting point. When you bring a body of revolution closer to the ground and add four wheels drag increases. That is what Alberto Morelli did to make a low drag body for the Fiat vehicle (131?). Nature never tires of surprising people.

[freebeard]

I like the fuselage of the ME-262, it has a triangular shark-like section. flat on the bottom, tumblehome for sidewinds and no appreciable upper surface to provide lift when you're sideways.

What happens when you turn the Template upside down? Colani's C-form.



Then when you cross the Template with Morelli, you get Ross Lovegrove:

[aerohead]

I spent two more weeks compiling and sharing data for my observations regarding the video, adding everything back at #8 ( permalink ).