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

[kach22i]

I agree with you guys about the dimpling location, looks to be an artistic expression more than an engineering solution.

Re-post from another thread regarding attachment.

NASA - Learning to Fly on Mars

Image above: In wind-tunnel testing, the inflated wing's "bumpy" profile improves aerodynamic performance by reducing flow separation in low-density, high-speed flight conditions expected for Mars flight. Credit: University of Kentucky

And an example of location specific dimples.

http://forums.pelicanparts.com/off-t...ml#post7660402

Originally Posted by widebody911

The Corbin Sparrow had golf ball dimples in the late 80's

This has got to be a low CdA yet high-ish Cd example below.

http://forums.pelicanparts.com/off-t...ures-1176.html

[kach22i]

Just an artist rendering, but a good one.

↑ The Playboy Land Yacht Concept by Syd Mead (1975)
The Playboy Land Yacht Concept by Syd Mead (1975) - Blog

... you'll see that the yacht's pointed nose serves two functions: It provides the aerodynamic styling that a machine of this size demands and it allows for the four lounge seats up front to be arranged at a 45-degree angle to the axis of the vehicle, thus saving considering interior space.

[euromodder]

Nothing aerodynamic about that land yacht ... other than it being an aerodynamic disaster.

[Cd]

Actually not bad considering some of Syds other stuff from Blade Runner :

[freebeard]

Syd Mead's pre-Segway


He also did the Tron motorcycle.

[kach22i]

Originally Posted by euromodder

Nothing aerodynamic about that land yacht ... other than it being an aerodynamic disaster.

The body tapers in at the back, the middle part being widest.

Beats the snot out of a straight slab sided RV still being produced today.

I'm not wild about the roof attachment.

I'll admit this Syd Mead thing falls way short of the Vixen though.

[freebeard]

Quote: Originally Posted by euromodder
Nothing aerodynamic about that land yacht ... other than it being an aerodynamic disaster.

The body tapers in at the back, the middle part being widest.

Beats the snot out of a straight slab sided RV still being produced today.

I can't find anything right now but those pictures reposted repeatedly, but the vehicle is something like 12 feet wide. Comparison to the Vixen is beside the point.

Self-driving in 1975, though.

I'd prefer Colani's effort

[shovel]

Unsure if powered or pedaled...

[NeilBlanchard]

^^^
That is a Quest and it is pedal powered.

[fidalgoman]

Originally Posted by euromodder

Looking at the angles of the roof, it doesn't need any dimpling for aero purposes.
Where the design might use them - like aft of the rear wheel arcs, where the bodywork falls of sharply - there are no dimples.

You don't want round shapes on the rear.

The thing that drives me a bit crazy is this whole dimpling thing. Golf balls have dimples because they are so small compared to the viscosity of the air. Very small dimples the size of the ones in golf balls might work on a small scale but not with golf ball size divots on automobiles, etc. Vortex generators work by creating low pressure areas and suck down the thick boundary layer to follow the profile. The more you work the air the more drag is produced. Sometimes it's on the positive side when detached flow is resolved.

Rounded in front with smooth pressure recovery profile in the rear. Most things are compromises for shape and space with true streamlining rare. Don't look at Racecars since they are more about down-force than pure drag reduction.

Reynolds numbers are the reason that aerodynamics is so different on the micro vs. the macro scale. Also there is a great deal of difference on what works aerodynamically at 0-100, 100-250 and 250 MPH up to near Mach speeds. There is a huge body of information out there.