Camper build using old Hi-Lo

[rumdog]

Originally Posted by freebeard

rumdog --

Your choices are curved, angled and stepped. They should all arrive at a cross-section falling on the template curve at the chosen truncation.

Yes well put freebeard! Me i like curved, but angled and stepped both work good too

Whats thoughts on turning vanes for front corners?

[freebeard]

I don't think turning vanes would be effective in the turbulent wake of the tow vehicle. How about half-rounding the edge like this [camper]:

[aerohead]

Originally Posted by Hersbird

The top set seem to apply more. Would a combination of the 3rd and the last pic be even better? I assume the last pic how's a side taper on the boattail, but what is the angle of that?

It would be superior.
The edge radii kill vortex formation.
The side walls are angled in at 10-degrees.
GM chose this approach for their 'OPTIMUM BOAT TAIL'.
Sorry,no data on it "TOP SECRET"

[aerohead]

Originally Posted by rumdog

Yes well put freebeard! Me i like curved, but angled and stepped both work good too

Whats thoughts on turning vanes for front corners?

Hucho tested turning vanes and they only added drag.

[rumdog]

Originally Posted by aerohead

Hucho tested turning vanes and they only added drag.

Well geez... i figured the round edge and a little surface friction and increased frontal area may be better than a sharp edge and the huge trailing eddie.
Ok so then freebeards rounded additions should help in this situation... on trailer front. Not sure how much they would help in full frontal flow?

[freebeard]

It's just a gimmick to get a radiused front edge without having to intrude into the structure. The benefit can be derived from aerohead's charts.

[aerohead]

Originally Posted by rumdog

Well geez... i figured the round edge and a little surface friction and increased frontal area may be better than a sharp edge and the huge trailing eddie.
Ok so then freebeards rounded additions should help in this situation... on trailer front. Not sure how much they would help in full frontal flow?

Here is a pictorial drag table from Walter Lay's research illustrating what a softened leading edge can do.
This research was repeated for the 1955 VW bus by M'o'ller,who gor similar numbers

Here,softened edges get Carr's brick Cd 0.21

Here's a trailer,very similar to Carr's wind tunnel,and similar Cd

[skyking]

reminiscent of a star trek shuttle

[freebeard]

ACTD - Advanced Starship Design Bureau | Shuttle Specs

It needs retractable pontoons. That could make it a catamaran houseboat,

[Hersbird]

Well I took a camping trip with the camper basically stock, 212 miles total up into the mountains, ran it from 55-65 mph (with some slower corners and 20 of the miles just across town and back), no traffic on a Tuesday/Wednesday and I averaged exactly 14mpg after refilling. I would normally be pretty happy with that as this is the best I have ever got towing anything except a Jetski behind my Subaru, but Now I want more. I may do some shorter runs just down the highway locally for 5 miles and see what the torque pro says the level, steady state 65 mph mpg is.

Now I'm ready to try a few aero/utility mods. I think I'm settled on a 2' long tail extension for storage and aero using unistrut and plywood covered with titebond II soaked fabric for the lower box to put stuff in with 2' high sides, with the top 1/2 built out of lightweight foam panels over 1/2" conduit covered with resin. Then the top part can raise with the factory hydraulic lifting top exposing the storage space under but otherwise keep water and prying eyes out of what is in there.

The front corners I plan on some 6" galvanized ductwork opened up into 12" 1/2 rounds to try and fake a radius front corner that really takes a hit from the wind coming off the sides of the tow vehicle (the camper is about a foot overall wider then the truck). There was some rain spray on the way home and you could see it really pushing out on the sides of the camper.

I also have a Styrofoam ball to cut in 1/2 for the front of the awning, and a Styrofoam cone for the rear of the awning. Might also add some Styrofoam wedges behind the roof vents.

Been looking for some free coroplast to try and skin the belly as well.

Also looking for some free time that I don't just say screw it and go fishing again!