Roof Spoiler on Pick-Up Truck Cab - Phase-1

[kach22i]

Originally Posted by aerohead

Reduced lift was a side benefit of the drag reduction.I don't have the paper with me so I can't give you any particulars.

If that is what you remember then I'm hopeful of doing more alternates on this basic design. I was under the impression that drag reduction typically means lift increases, and that drag increases are related to down-force generation.

Of course, there are always exceptions to the rules, and that is where my energies will be focused.

[SvdM]

Nice project. I have something similar planned for early 2012.

[kach22i]

Originally Posted by SvdM

Nice project. I have something similar planned for early 2012.

Great, I'm convinced there is great potential for increased safety with this approach, still working on that "saving gas" part myself.

When I hit potholes the wing does rock and tap on the roof a little, so those extra roof screws are going in soon.

The few times I've driven with ice and snow filling the gap I could have sworn there was less down force. I will need to foil tape the gap in the spring and do some real testing. Right now I'm pretty happy where I'm at on this project.

I just hope my vinyl bed cover survives the winter, this is the first winter I'm leaving it on.

EDIT: One inch of snow, sitting overnight and all day in dry air, driven at 45 mph for 1-2 miles to the gas station. There was quite the dust devil of swirling going on as I looked in my rear view mirror. Here is the resulting pattern it left.

S10 4x4 Pick Up pictures by kach22i - Photobucket



To my eyes; the vortex of air coming off the cab corners is intact and healthy. The mysterious middle scoop of missing snow, and small drift against the glass might be the trapped vortex of rotating air I've shown in an earlier diagram.

I should note that the snow was only brushed off the front windshield and hood, the roof snow and tonneau cover snow was left virgin prior to driving off.

EDIT 12/10/11
S10 4x4 Pick Up pictures by kach22i - Photobucket


http://s184.photobucket.com/albums/x...4%20Pick%20Up/

[kach22i]

This VW Bug wing seems to have a few similarities to my own little experiment. I'd sure like to see a wind-tunnel of this to see how the gaps are contributing.

Automobile pictures by kach22i - Photobucket

[Sven7]

Originally Posted by kach22i

To my eyes; the vortex of air coming off the cab corners is intact and healthy. The mysterious middle scoop of missing snow, and small drift against the glass might be the trapped vortex of rotating air I've shown in an earlier diagram.

I should note that the snow was only brushed off the front windshield and hood, the roof snow and tonneau cover snow was left virgin prior to driving off.

That's some great real world experimentation right there. I reckon with the spoiler pointed down 10 degrees and some buttress type fairings on the side it could really reduce the wake you're seeing on there. Of course you probably won't get the extra downforce of your current spoiler but you'd get gas savings! There's a thread somewhere of a Toyota Sienna with the side fairings. I'm not even going to attempt finding it.

[kach22i]

Originally Posted by Sven7

That's some great real world experimentation right there.

The basis of all science is observation (and experimentation), right? Once you learn to keep your eyes open, you will see many things which you would normally not.

I did not plan nor expect this to happen, but when I was walking toward the truck that morning I had a hope, and that hope was confirmed.

Phase II?......smaller less energy robbing vortexes?
Industrial Design - Transportation pictures by kach22i - Photobucket


Boeing 737 Advanced Blended Winglets




As The Croft Flies: December 2010 Archives

#MEBA10: Winglets 101
By John Croft on December 6, 2010 12:36 PM

Walking the ramp here at the Dubai International airport on the eve of the Middle East Business Aviation (MEBA) show, I happened on a good example to show the difference between blended winglets and elliptical winglets.



Blended winglets are the intellectual property via patent law of Seattle-based Aviation Partners..

Elliptical Winglets are the intellectual property via patent law of Wichita-based Winglet Technology, the founder of which used to work for the former.

Needless to say, they don't like it when you get the two technologies mixed up, despite the fact that both increase maximum load and increase cruise range.

So here's the deal:

Blended winglets as seen on the Boeing Business Jet (B737) in the background consist of a straight winglet joined to a straight wing via a curved joint.
Elliptical winglets, shown in the foreground on a Cessna Citation X, consist of a constantly curving winglet joined to a straight wing.
.

[kach22i]

Phase III...............winglets/fins on rear

Inspiration.
GALLERY>>ICONIC PORSCHE LIVERIES - Speedhunters

The Porsche 917 is a beautiful car, even better in coupe trim. In 1971 Porsche commissioned an Aerodynamics company, SERA to analysis the 917 and develop a more efficient car. The organisation discovered that by making the car wider, the wheels would be inboard and be create less turbulent air. The car made its debut at a test in plain white. The bulging bodywork with the inset wheels reminded journalists of a Pig with its relatively small feet and thus, the idea of the Pink Pig was born.

One possible application; Scheme 4-Corner Winglets
Industrial Design - Transportation pictures by kach22i - Photobucket


EDIT-1
At the risk of sending my own thread into the "Off Topic" zone, I post this.

Saab: phoenix at geneva motor show 2011
saab: phoenix at geneva motor show 2011

Based on a highly aerodynamic, 'aeromotional' design that highlights the aviation roots of the company,
the car features a low front and cabin, which flows into a hood and tapered rear deck.
side and roof-mounted winglets, modeled after the flying buttresses of architectural planning,
channel airflow from the sides of the vehicle across the rear deck to reduce lift.

These winglets or what every they are, seem to form a second skin which controls vortex formation.

Perhaps a hollow cylinder, half cylinder or hoop which is aerofoil in section and set at the locations I've already indicated would work at controlling vortexes.



EDIT 12/13/11
Something like this on the back of a pick-up truck cab would be clean and simple.

http://www.fitfreak.net/forums/gauge...o-spoiler.html


EDIT again 12/13/11..............more fins on a car.
http://www.metaphorsinmotion.com/pos...-Chaparral-2-C



EDIT .....................wild thing.
http://forums.nasioc.com/forums/show....php?t=2233025


EDIT.....this may actually work - who would have thunk?
http://www.indiancarsbikes.in/auto-n...tures-2-18171/

[aerohead]

See if you can find an image of Ferrari's 599 XX car.It has C-pillar buttress winglets which help get air onto the rear spoiler with minimum drag.
They spent a couple hundred hours in the wind tunnel ( $2oo,ooo) to dial them in.They would be an example of current-think which actually performs.
You're going down a lonely path.There's very little literature on such things.Good luck!

[KamperBob]

Kach22i. when I look at the snow pattern on your tonneau it seems intuitive. Snow deposited behind the cab could be explained by a pair of mirror symmetric separation bubbles. Think about boundary conditions and flow balance as a visual. Flow wants to converge convexly over the bed. Given the rear wing likely reattachment there. In between lies a typical open bed bubble but shallower due to the raised bottom with the tonneau and, moreover, cleaved down the middle by forward flow. The forward stream could drop its load up against the back of the cab in the sharp turns and reduced velocity. (This same principle is used in wood working in the form of a chip separator can before the dust collector bag on table saw exhaust port for example.) The assymetry left to right could be explained by a bit of cross wind effect. I'm skeptical about much roof corner vortex because that edge is radiused a couple inches, but experimenting will tell for sure. Either way I look forward to more. Nice contribution. Rock on!

[kach22i]

Thanks for the leads and encouragement guys.

Ferrari 599XX side wing photo



Ferrari 599XX winglet Wallpaper | Walltor


EDIT.....some more ideas floating around in my head, Stratos inspired.

http://s184.photobucket.com/albums/x...4%20Pick%20Up/



EDIT-2............this plane fence gives me ideas.
http://www.a2wt.com/Pictures.htm


EDIT-3: ....another roof wing
http://www.iwsti.com/forums/gr-vendo...-2008-sti.html



...........and another.
http://www.iwsti.com/forums/styling-...-all-sale.html