Silverado aerocap build thread

[aerohead]

Originally Posted by TechStuf

Yes. All except for the words, 'any' and 'only'.


Careful study of the lowly Bacterial Flagellum reveals some amazing design considerations, as they employ virtually 100% efficient electric motors and propellers by which to effect locomotion.

Notice the design and placement of their propeller filaments, particularly in the E Coli bacteria.



It's all there in nature. Everything. By design....the opportunities to reverse engineer what has already been created are mind boggling.


TS

Techstuf,I'm having difficulty making the leap,from a bacteria within the environment of the human alimentary canal,and the potential of harnessing it's form of locomotion for the purpose of extracting usable energy from the airstream regime between a pickup trucks forward stagnation point and turbulent wake during operation up to and including 80-mph ( I believe the upper legal speed limit in the continental U.S.) without increasing drag.
The E-coli would be moving within a relatively 'stationary' media,yes?
The delicate cell structure of their locomotive structure unsuited to the rigors of 80-mph turbulent airflow?
MIT,so far,has struggled to bio-mimic the propulsion of a bluefin tuna with 'robo-tuna',a much larger hydrodynamic structure,an undertaking which would appear a 'walk in the park' compared to that of reverse-engineering a leviathan bacteria.Yes?
Please help.I'm not the sharpest knife in the drawer and I'm grappling to understand your concept.

[Frank Lee]

What- you are having trouble imagining vehicle-sized flagella convulsing down the roads?

[aerohead]

Originally Posted by Frank Lee

What- you are having trouble imagining vehicle-sized flagella convulsing down the roads?

Frank,I put on my lion-tamer costume,pried opened my septic tank,and with some coaxing with chair and whip,got some E-coli onto the back of the truck.But(t) from there it was all downhill!
I gotta tell ya,it will really mess with your self-confidence! And clothing!
Anyway,after a few futile hours of 'training' I threw in the gloves,determining I wasn't up to the task of developing this --itty new form of locomotion.
I also learned from the old plumber axiom,'don't bite your fingernails.'

[sid]

ChazInMT: I took pictures of my topper during the build process, but apparently I haven't taken any pictures yet of the completed topper. After I take those pictures, I think I'll start a new thread about the build process of my topper, rather than taking over someone else's thread. It may take me a week to write it up.

But it is just a straight cab-high topper, not a slanted one like most often discussed here. I use my topper almost every time I use my truck, so I want a light topper with a certain minimum size (for camping in and for carrying my musical instrument gear; a slanted topper wouldn't work).

Big Dave: I got the Trim Lok (this is the correct spelling) from a local fiberglass materials supplier (Fiberglass Coating, Inc.) here in the Tampa Bay area. You can search "Trimlock" and the parent company (Trim Lok - #1 Source for Plastic and Rubber Trims and Seals) will show up.

[ac7ss]

Reminder to all you amateur aerodynamicists out there: Air behaves like an INCOMPRESSIBLE FLUID below the speed of sound. (This is why we don't have pointy ends on subsonic aircraft.)

[dmac257]

Originally Posted by Fubeca

Thanks to everyone for all the encouragement! It was fun to build and I think it will serve its purpose well. If I can find some time on a day without wind (we get one or two each year), I'll try to take some video of tufts and see what the air is doing.

How do you video tufts .. and tufts of what?

Don

[dmac257]

Originally Posted by ChazInMT

Hey Christ, Thanks for that heads up. I was considering putting in a clear area on my build but you just save me a ton of time and I'm sure aggravation trying to get a "View Port" in there right.

Strange, IMHO, you can't make it too steep if you go from the back of your cab roof down to your tailgate top. You do want to be sure to make it a curve shape. Your aero cap will have a flat area on top just behind the cab and will have it's steepest slope just in back above the tail gate. Air flow hates any sudden changes here.

So which would be better a smooth gentle slope directly from the cap to the tailgate simular to Fubeca's or one that starts flat and forms a camelback with a sharper curve and less sharp separation angle at tailgate. I have seen both. Is a full cap better than a tanneau cover? I also have a short bed pickup and want to replace my tanneau with better cover and commercial cost is making a DIY construction REAL attractive.

Don

[aerohead]

Originally Posted by dmac257

So which would be better a smooth gentle slope directly from the cap to the tailgate simular to Fubeca's or one that starts flat and forms a camelback with a sharper curve and less sharp separation angle at tailgate. I have seen both. Is a full cap better than a tanneau cover? I also have a short bed pickup and want to replace my tanneau with better cover and commercial cost is making a DIY construction REAL attractive.

Don

Don,there's an "Aerodynamic Streamlining Template' you could do a search EcoModder.com for.
If you will scale an image of your truck to fit under it as illustrated,it will design your cap for you.It's what it's for.

[miket]

how about we use that suction energy thats going to pumping losses to run hybrid laminar flow control like boing is doing on the tail of the 787-9.

http://www.aviationweek.com/aw/blogs...entId=blogDest

[aerohead]

Originally Posted by miket

how about we use that suction energy thats going to pumping losses to run hybrid laminar flow control like boing is doing on the tail of the 787-9.

787 - tail wagging the dog

Laminar flow would be a setback to us if you're discussing boundary layer as would be addressed with a wing section.
The wing has no separation issues and it's drag is governed by skin-friction,something a laminar boundary layer would help.
Cars have separation issues,there drag is predominately pressure-drag which benefits from a turbulent boundary layer,and if we had a laminar boundary layer we see even higher drag.
It is true,that if we could provide enough suction near the back of a car,it's profile could be steeper,without separation,but so far,the energy required to provide the suction exceeds the energy saved,not true for the suctioned wing which can withstand departure angles as high as 40-degrees as with the experimental Gottingen suction-slot/flap wing.