BEST + CORRECT Aerodynamic Streamlining Template

[slipknotsv]

Which is the best aero of all and correct Old VS. New

Tesla vs. Old






old....












best of + correct Template all....

Thanks for help...

[ByDesign]

It's a good question. I like the concept of superimposing these shapes over photos, but it's a bit misleading in some respects.

There is no "best" shape for all vehicles. The blunter one would be better for a little lower speed. I have no idea what speed that is compared to the Tesla version, but that's the direction. The faster you go (within limits), the longer the aspect ratio to be optimum. Also, as we superimpose the shape it counter-assumes the vehicle purpose. Some vehicles just need to be taller or longer to fill their function.

Finally, beware of the 2d limitations in thinking when viewing shapes like these. Sides of the vehicle are just as important -and ground effect too.

[freebeard]

ByDesign has correctly summarized the tyranny of Thee Holy Template.

Tesla vs. Old

[citation needed]

[slipknotsv]

best template is ..........? from these? Recommendations and most accurate.....

[kach22i]

Originally Posted by ByDesign

Finally, beware of the 2d limitations in thinking when viewing shapes like these. Sides of the vehicle are just as important -and ground effect too.

Yes, true - true - true.

One thing I've noticed in many of the wind-tunnel videos I've watched is that the stream of smoke which actually manages to go over the roof seems limited to one 4-inch wide spot dead center on the upper lip of the front grille.

A notable amount of the smoke coming out of the wand/probe goes off the top of the side windows and an alarming amount get blasted at the side view mirror area with just slight off-center locations.

Going back to the plan view importance; based on the smoke tunnel videos it appears that just about 1/4 the air mass, 1/8th each front corner runs along the lower sides of the vehicle.

Makes sense if we allocate the air pattern as seen in the attached marked-up (by me) photo.

MORE random pics...... - Page 3858 - Pelican Parts Technical BBS

[kach22i]

In the watermelon image posted I can visualize the car in the melon.

I can see very little air going over the center-line, and all that air hitting the mirrors at the quarter-line.

I can see the top of the side windows being the point where a battle to equalize air flow pressures ensues.

I can see a small amount of air going along the sides.

[aardvarcus]

Doing some overlays in the past, I noted that several low drag Toyota cars fit AST-2 pretty well. Honestly the difference between the two templates mentioned is so slight, I am not sure how you would pull off building one versus the other without specialized equipment.

As others have mentioned the AST-2 side overlay template is just a starting point in one dimension, however it is a really good starting point for those of us who wouldn’t have a clue were to start without it.

The hard part is actually going out and building something. It really doesn’t take that much creativity to start with a 2D view/print and figure out a decent (but non ideal) 3D shape that will work for your vehicle and your intended purpose. Personally, I am shooting for a shape that is “not as terrible as it used to be” which is within the realm of my abilities (I hope) and tools (as I am presently wind tunnel deficient). Actually implementing that by building something is where the work is.

There is a top overlay and rear view of the AST-2 vehicle that have also been posted, which with a bit of imagination describe the AST-2 “vehicle” in full 3D. It is probably "too ideal" for direct implementation on typical boxy vehicles.

[slipknotsv]

best Template AST-2........ ?

We wait for statement Aerohead.....

[Frank Lee]

There are some horrendous looking, lumpy vehicles (aerocivic, illuminati seven) that claim ridiculously low Cd so perhaps strict adherence to a profile is not as critical as one might think.

[slipknotsv]

next........