Quote:
Originally Posted by ecoromer
Seeking wisdom from the experts over here.
I'm in the final design phase of an overland camper build. I have a design that I feel is structurally, mechanically, and ergonomically well put together. And while the vehicle has been built to travel anywhere, it still spends most of its miles on long stretches of highway. And so, I feel it's important that it's not shaped like a box 
I've played with overlaying a variety of streamlining templates over the model, scoured the webs for similar shaped vehicles in wind tunnels, and tinkered with the overall shape until it stopped being ergonomic.
The vehicle is driven between 50-65mph, normally a few hundred miles at a time.
My research points toward the most gains from: - Fairings between cab and camper
- Arched roof
- Modified boattail
The dry weight of the box will be comparatively light, less than 800lbs. The entire structure is constructed of fiberglass reinforced panels (FRP), foam for the exterior and PP honeycomb for the interior. Similar construction methodology to many boats.
And so, studying the attached model, what would you do and why? |
*For their 'Bat Truck' 18-wheeler,and 'Shoebox' Ford Econoline-based van streamlining,NASA chose leading-edge radii equal to 20% of the vehicle width.
*They brought the sides down level with the belly.
*They did a full belly pan.
*This got them from Cd 0.89,to 0.347.
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*With their truncated boat tail,she went to Cd 0.242.
Out in the boondocks,I don't know what you can get away with,clearance wise.The NASA numbers would give you a sense of what's doable.
*You might have to cantelever the 'nose' of the camper beyond the cab a bit,use the bottom of it as a splitter,to direct the flow down there to the sides as you see in some commercial box truck applications.
*Wraparound front airdam to properly get flow onto the new 'sides' of the rig.