FLOW-IMAGES ( brain food - various wind tunnel, tuft testing, smoke trace images)

[aerohead]

Originally Posted by MetroMPG

Thanks Phil! Is the EV1 image coming, or do we need to wait 3 weeks?

Happy holidays to you too. Good luck with the trailer, and thanks for all the brain food.

Darin,man I'm really sorry! I did another session with the photos,and EV-1 was supposed to the the first one out of the shoot.
Al says he can do it today.I've been focused on the Viking and deadlines and my thinking is in another universe.Hang on!

[aerohead]

Originally Posted by NeilBlanchard

Thanks for that -- so a Cd of 0.20 is not as good as the the various GM and Ford cars that are of a similar size. And it's fugly...

Neil,the thing for me,is that it's 1979.This was a big deal.Dr.Morrelli used pure science to create the car.
The crushed-Omega design offers zero-lift,something Hermie appears to be obsessed with,and without the addition of the ubiquitous stabilizing dorsal fin of past times.
The car also had to respect many legal limitations for bumper height,pedestrian safety,headlight height,license plates,etc.
This car remains the benchmark for cooling system low drag.
The car was "producible" which cannot be said for many concepts and does not rely on active suspension for it's low numbers.
I consider many contemporary low drag concepts to be "rip-offs" of Dr.M's designs.

[MetroMPG]

The Morelli car is fantastic. The only sad thing about it from an ecomodder's perspective is it's practically impossible for a DIY aero enthusiast to use duct tape and cardboard on our existing cars and end up with anything remotely close to that shape!

[aerohead]

I apologize for delay on this one,as at Cd 0.188 the EV-1 has generated a great deal of interest at the Aero Forum.
My interpretation of the photo,is that the car does suffer flow separation over the backlight and boot,as the smoke overides the structure and initiation of turbulence is evident with the swirling smoke trace.
In GM's defense,from previous articles it has been reported that GM has very stringent and rigid internal standards for outward visibility for the driver which may have precluded the use of a more gentle angle at the rear.
Aerodynamically,the tip off would be the metric of the car at Ft.Stockton,setting the LSR,where the "Yellow Ferret" aluminum boat tail cone is used with an included exit angle of 9-degrees,which when measured from tip to roofline,gives the back of the car a 15-degree angle,oddly,not as radical as the Mair' 22-degree aggressor.

[Tygen1]

Do you have any pictures of the EV1 boat tail?

I'd be satisfied with a scetch on a napkin

[thatguitarguy]

You can break out a napkin and DIY...

Look kinda like an Insight...

[aerohead]

Originally Posted by Tygen1

Do you have any pictures of the EV1 boat tail?

I'd be satisfied with a scetch on a napkin

Tygen1,I've got two shots of the tail plus a video of its install and the record runs at Ft.Stockton.
The picture we need to look at I have made a digital image of,will enlarge,cut out,and place on a neutral gray background.
The photographer used some crazy "dramatic" effect with this shot and it makes it very difficult to "see" the car.
Christ has this photo and posted it at a different thread,but I don't remember where.Sorry.
I'll do this image but can't say when.
What I can tell you is that the tail's descending angle,measured from the horizon,is 9-degrees ( one degree less than what Dr. Kamm recommended ).The sides of the cone basically follow the angle established by the cars boattailed flanks ( an overhead view of a blue EV-1 is in the "IMAGES" somewhere )
When the tail is on the EV-1,the angle,measured from the end of the tail,up to top of the roof creates a 15-degree angle.
Hope that helps get you off dead center.

[Tygen1]

Heres' the only two imgages I could find...

[aerohead]

Originally Posted by Tygen1

Heres' the only two imgages I could find...

Those are the two that I have.The side shot is close to a "true-length" image,as you would get with a blueprint of the car.
Any measurements and angles from it should reflect very closely what the car embodies.
With that,and the overhead view from the FLOW-IMAGES Gallery you should be able to do a pretty complete reconstruction.

[thatguitarguy]

Maybe this helps.