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

[The Toecutter]

Originally Posted by aerohead

When Dr. Michael Seal was running the automotive research at Western Washington University, their 'Viking' series of hand built cars were exploring this territory.
The numbers are for the taking!

I'm familiar and have read about them nearly 20 years ago when I was in college. They're not quite on the level of the aforementioned MG streamliner, but they're a massive improvement over anything the modern auto industry has put out let alone anything from back then! About 15 years ago I was compiling an article on fuel efficient cars from the 1930s onward, which never got completed or published, and I had all my sources of info saved from then. The links are likely defunct, but that's what archive.org is for.

Viking IV


The 1978 Viking IV was powered by a 1.5L 4-cylinder diesel from a Volkswagen Rabbit[1], producing 48 peak horsepower[2]. The car weighed a mere 1,250 lbs[3]. In 1981, the Viking IV was able to average 87.5 mpg during a rally that spanned the continental United States[4]. According to the car's builder, Professor Michael R. Seal, it was safe enough for the occupants to survive a 50 mph head on collision[4]. In 1982, the car was tested at the GM proving grounds and the Transportation Research Center of Ohio, yielding 73 miles per gallon at a steady 70 mph[4]. It was later upgraded to make use of low rolling resistance tires, a 5 speed transmission with overdrive, and a 1L, 3-cylinder turbo diesel. This allowed it to achieve 100 mpg at a steady 50 mph[5].

Viking VI


The Viking VI was built to achieve high fuel economy while exceeding the crash safety standards that were in place; it achieved 118 mpg at a steady 50 mph[5] .

Viking VII


The Viking VII took this concept even further, proving that high fuel efficiency, safety, and high performance could exist within the same vehicle. It was able to accelerate from 0-60 mph in 5.3 seconds, achieve over 1G on a skid pad, and still manage 50 mpg highway[5]. It was driven to a top speed of 186 mph on the Bonneville Salt Flats[6]. It made use of a 4 cylinder DOHC Boxer engine which produced 133 horsepower. These features of high performance, adequate safety, and high fuel economy could coexist within the same vehicle due to a low drag coefficient of only 0.26, a small frontal area, a lightweight composite body, and an aluminum chassis[7]. The performance of this car rivaled some the fastest production cars of the era; for comparison, the legendary Ferrari Daytona did 0-60 mph in 5.3 seconds and had a top speed of 175 mph[8].

Avion


None of the Viking Research Cars have ever reached production. The Avion, modeled off a previous Viking Research car and designed by former VRI student Craig Henderson, was perhaps the closest any of the cars came to being produced[9]. While the car only achieved 40 mpg combined, it could reach a top speed of 135 mph and accelerate from 0-60 mph in under 6 seconds using a 4-cylinder engine from a 1980s model fuel-injected Audi[10]. This combined performance and fuel economy was possible thanks to a 0.27 drag coefficient and a curb weight of only 1,500 lbs[10].

References:

[1] Avion. (1986). Would You Believe 88.2 mpg?. Retrieved August 6, 2007, from http://www.100mpgplus.com/articles/m...le_unocal.html

[2] Edmunds Inc. (2003, January 1). Volkswagen Golf Rabbit. Retrieved June 23, 2007, from http://www.edmunds.com/insideline/do...ticleId=105265

[3] Avion. (1986). Would You Believe 88.2 mpg?. Retrieved August 6, 2007, from http://www.100mpgplus.com/articles/m...le_unocal.html

[4] Kocivar, B. (1982, January). Low-drag cars get 100+ mpg. Popular Science Magazine.

[5] Vehicle Research Institute at Western Washington University. (2006, September 19). VRI History. Retrieved June 22, 2007, from http://vri.etec.wwu.edu/history.htm

[6] Tour De Sol. (2004, June 12). The Tour De Sol Reports, 2004. Retrieved June 23, 2007, from http://www.autoauditorium.com/TdS_Reports_2004/

[7] Seal, M. R. (1985). The Viking VII: a lightweight research vehicle. SAE, 850101. Warrendale, PA: Society of Automotive Engineers.

[8] QV500. (2007). Ferrari Daytona Part 1: 365 GTB/4 & GTS/4. Retrieved June 23, 2007, from http://www.qv500.com/ferraridaytonap1.php

[9] Avion. (1985). Designing the car of the future: Small & simple is the secret of a WWU project. Retrieved August 6, 2007, from http://www.100mpgplus.com/articles/n...icle_0003.html

[10] Avion. (1985). Rocket on wheels: Experimental car set world record for fuel. Retrieved August 6, 2007, from http://www.100mpgplus.com/articles/n...icle_0001.html

[freebeard]

Good post. I know a high stagnation line was popular back then, my first car was a bullet-nose Studebaker. But modern practice is to shroud the front and sides of the underbody.

What made the difference? Was it previously a holdover from nautical practice?
_______________

I like the Horbacher stuff, especially the slide-back canopy on the Egg. It just needs a shark mouth and campaign stripes.

Actually, it's a 1980s precursor of the Arcimoto FUV. I think I'll send the picture to their 'Customer Experience Manager'.

edit:
Done, I'm adding skegs to my design to accommodate a slide-back canopy.

[Bicycle Bob]

Originally Posted by freebeard

Good post. I know a high stagnation line was popular back then, my first car was a bullet-nose Studebaker. But modern practice is to shroud the front and sides of the underbody.

What made the difference? Was it previously a holdover from nautical practice?
_______________

No, it was styling intended to evoke aircraft design, where incidental lift was a good thing. We have also had strong trends aping the appearance of supersonic aircraft with their sharp leading edges. It took a long time for engineers to figure out underbody flow and how to avoid lift. Now, we still get styling copied from racers that maximize downforce, not streamlining, and leave the bottom rough for easy service.

[The Toecutter]

Renault EVE



Renault unveiled their EVE concept car in 1980. The EVE was built on a Renault R18 chassis, used a supercharged 1.1 L inline 4-cylinder supercharged diesel engine, and had a 0.239 drag coefficient[1]. This engine output a maximum of 50 horsepower[2]. The curb weight of the vehicle was 1,900 lbs[2]. The combination of these traits allowed it to achieve 70 mpg combined fuel economy[2].

Renault EVE+

Expanding upon the previous concept, the Renault EVE+ concept car was revealed to the public in 1983. It used the same 50 horsepower diesel engine as the EVE, but had reduced the curb weight to 1,880 lbs, had reduced the drag coefficient to 0.225, and achieved 63 mpg city, 81 mpg highway[3].

Renault Vesta



While the diesel Renault EVE concept cars were being developed and tested, Renault was also working on their gasoline powered Vesta concept cars. The Renault Vesta was revealed to the motoring public in 1981. It had a weight of 1130 lbs[4], a 0.25 drag coefficient[5], and a top speed of 75 mph[6]. The Vesta's fuel economy is 78 mpg[7].

Renault's next generation of their Vesta concept car had reduced weight and reduced aerodynamic drag, which improved fuel economy and top speed. The 1987 Renault Vesta II weighed only 1,047 lbs, had a 0.186 drag coefficient, a 27 horsepower engine, and was able to return 78 mpg city, 107 mpg highway[8]. Its top speed was over 80 mph[9].

References:

[1] Renault Club. (2007). 1981 – Renault EVE. Retrieved June 27, 2007, from http://www.renaultclub.cz/1981_-_renault_eve.html

[2] Saxon, D. (1988). Technology and the American Economic Transition: Choices for the Future. U.S. Congress, Office of Technology Assessment, OTA-TET-283. Washington, DC: U.S. Government Printing Office.

[3] Bleviss, D. (1988). The New Oil Crisis and Fuel Economy Technologies. New York: Quorum Books

[4] Parliament, UK. (2003, October). Memorandum by Stephen Plowden: Cars of the Future. Retrieved June 27, 2007, from http://www.publications.parliament.u...19/319we06.htm

[5] Philippe B. de l'Arc – A coeur vaillant, rien d'impossible. (2007). Aerodynamic Drag, Data for airfoils, Wings, Aircraft, Automobiles. Retrieved June 27, 2007, from pboursin.club.fr/res/aero.xls

[6] Parliament, UK. (2003, October). Memorandum by Stephen Plowden: Cars of the Future. Retrieved June 27, 2007, from http://www.publications.parliament.u...19/319we06.htm

[7] Greenpeace. (2005, December 5). SmILE – Showing Car Companies How it's Done. Retrieved June 27, 2007, from http://archive.greenpeace.org/climat...rts/smile.html

[8] Bleviss, D. (1988). The New Oil Crisis and Fuel Economy Technologies. New York: Quorum Books

[9] Forza Mondo. (2006, August 20). L'Auto del futuro. Retrieved June 27, 2007 from http://forzamondo.blogspot.com/2006/...el-futuro.html

[freebeard]

Nice boxed cavity on a '66 Chevelle:


https://youtu.be/qC5M9EVe8M8

[kach22i]

I cropped Liz's photo, nice photo when seen in full view via the link.

https://gregwilliams.ca/tag/bonneville-salt-flats/

The Rod Shop’s Wingin’ It lakester. Liz Leggett photo.

Ralph's picture.

bonneville salt flats, land speed racing, SCTA-BNI, auto racing
https://www.pinterest.com/pin/369576713162279487/


Yea, the open wheels are huge sources of drag, but come on, these are cool.

[freebeard]

Open wheels is a use case, and therefore beyond reproach.

[Bicycle Bob]

Open wheels are required in that class, but I'd shop a lot harder for low drag models.

[freebeard]

Is Aptera open-wheel or no?

[aerohead]

Originally Posted by freebeard

Is Aptera open-wheel or no?

General Motors parsed versions of their FIREBIRD -I concept during aero testing as 'fendered' or no. The rear wheels were partially enclosed already.
Aptera is borrowing from 'Sylph', with semi-enclosed front wheels and fully-enclosed rear.