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Old 01-15-2013, 10:28 PM   #9 (permalink)
Tesla
Master EcoModder
 
Join Date: Feb 2012
Location: Australia
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The Truck - '02 Nissan GU Patrol ST
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Quote:
Originally Posted by aerohead View Post
They'll be dozens of solutions.Just like automatic coffee makers.
The thing I kept attempting to be as smart as,was all the possible deflections and their orientations such that I'd never find any of the structures binding or colliding.
I experienced almost daily failures when in early testing.
If you can get your trailer onto wheel dollies,where you can observe full range of motion side to side,while anticipating pothole and pressure ridge airborne antics.
It's like a monkey ______g a football.
What do you mean about "pressure ridge airborne antics"?
Is that to do with varying vortexes and pressures causing oscilations and unwanted flap?

Some sort of flexable/deformable gap filler would be ideal as long as it didn't flap around in the wind.

I have started thinking about ideas for the "ever elussive" inflatable gap filler/boattail idea, just read through some old discussions on the topic:
http://ecomodder.com/forum/showthrea...ack-22480.html

Seems the biggest hurdles are:
Inflation & deployment system.
Maintaining appropriate shape.
Minimising oscilations.
Fabric durability.
Simple attachment & removal for utility.

Would shade cloth be a suitable external skin "aero wise" as it is a fairly course weave?
From what I have read all indications are it should be fine as I have seen many comments suggesting that in reality we are actually moving turbulant air all the time so finer details of skin surface are irrelevant, the basic form is what is important.

*I'm thinking if one were to make the outer skin out of this type of material, it is cheap, strong & durable and is often used on the front of trailers as a stone deflector to minimise paint damage.
*Then use a lighter weight material internally to create a grid pattern lengthwise so individual inflation tubes could be inserted, visually looking into it like a case of wine, 12 individual bottles each in its own compartment.
*The inflation tubes could just be a suitable length and cross section of plastic tube sealed at one end and inflation tube attached to the other end.
*All tubes connected to one inflation manifold, where you can have one way valve, inflate/deflate etc.
*Use a duct from the front stagnation point, highest pressure on vehicle is there I imagine, supplementary blower if required. I could probably duct 2-3" flexitube without increasing frontal area on my car.
*Mount on vehicle side with a solid frame of appropriate design and angle to begin boattail shape.
*Trailer rotates around shape deforming as required, maybe a slip sheet of thick plastic attached flat on trailer face to protect trailer finish.
* Have one larger cell (or multiple) in the centre with a large rubber balloon attached to the manifold, this would remain deflated in normal operation, but when the trailer was turned hard the pressure from the compressed cells would inflate it temporarily until vehicle was in straight line again.
*It is a relativly low pressure set up < 3 psi most likely, aim to use commonly available materials to keep cost, but moreso inevitable maintenance down, one way valves can easily be made with ping pong ball, rubber O-ring and PVC pipe fittings, the pump/fan would be a negative, best avoided if possible.
*HD zippers, like on tents or larger luggage bags, could be incorporated for easy attachment and removal etc.

That's today's idea, see what else comes along.
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