Teardrop trailer campers

[Fat Charlie]

I've considered it. I've proposed it. I've let it go.

[freebeard]

Just A Car Guy did a post on:

Just A Car Guy: Teardrop history



...and:

Just A Car Guy: Teardrops made from WW2 bomber aluminum, with wheels from Jeeps salvaged from sunken ships. True WW2 worker ingenuity

[California98Civic]

Beautiful.

[freebeard]

Here is a well-done teardrop.

Outlast the Rest: Trailer Built to Last 40 EXTRA YEARS!

With a monocoque box on a flexible subframe, the Model 560 shape follows Wally Byam's pre-Airstream teardrop.



Routing the side panels for wiring runs under an aluminum skin could work with a foamie.

[j-c-c]

Regardless, how aero really is that marketed "teardrop" shape?
Any actual wind tunnel numbers to back up the trailer design?

[freebeard]

Aerodynamics isn't the strong point, but they are certainly better than a 'canned ham'.

It's why Airstreams are shaped as they are today. Compare the height of the cited example to the Byam prototype.

I posted it because they put the hulls on a rotisserie.

[j-c-c]

I think the marketing potential has been proven that "teardrop" outsells "canned ham", regardless of Cd. The "airstream" is another winner in this game. Me, I want numbers.

[j-c-c]

Originally Posted by freebeard

Here is a well-done teardrop.

With a monocoque box on a flexible subframe, the Model 560 shape follows Wally Byam's pre-Airstream teardrop.



Routing the side panels for wiring runs under an aluminum skin could work with a foamie.

I like the wire routing solution, except it is a huge stress riser in a monocoque structure. that rests on an admittedly flexible sub frame.

[aerohead]

I've seen one published Cd for an RV travel trailer since 1974. And it wasn't a 'teardrop.' This trailer was depicted, being towed by a Honda Accord, and there was no attribution specificity as to whether their Cd was ,measured as a tow vehicle/trailer 'system', or as the trailer in a wind tunnel by itself. No 'context', no 'conditions.' No 'actionable' information.
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Wolf Hucho's 2nd edition,' Aerodynamics of Road Vehicles' is the 'richest' single source for trailer data I've seen.
And the 'trailer' discussions here at EcoModder include all of it, plus everything published in the public domain, flagged by members over the decades.
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As to 'teardrop' trailers:
Baron Reinhard von Fachsenfeld personally measured the drag of a 'solo' structure which closely resembles the architecture of 'classic' teardrop trailers, recording Cd 0.45, at either Braunschwieg Technical University, or at Dr. Kamm's, FKFS, next door to Daimler-Benz, in Stuttgart.
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Such a Cd is 'useless', divorced from the effects of the tow vehicle ahead of it.
And since there's an 'infinite' number of potential TVs, along with an 'infinite' number of RVs, it would bankrupt a manufacturer attempting to 'cover the entire field' of combinations.
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All we can do is to compare 'solo' mpg of a TV, to it's mpg while towing a specific TT, then overlaying the frontal area footprints of the two, together, come up with an AF of the 'system,' plus it's all-up weight; then calculate the increased rolling-resistance, factoring that into the energy balance for the 'rig, allowing a constant BSFC, or BSFC-e for the tow vehicle.
From this, the Cd, and CdA of the 'rig' will fall out from the math.
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Just calculating the frontal area of an 'Airstream', 'Argossy', 'Casita' ,'Happy Camper', etc. can set you back half a day.

[j-c-c]

So the takeaway here is the Use of the label "teardrop" is mostly marketing.
The tradeoff in lost usable interior space and manufacturing efforts to achieve the "teardrop" persona are yet to be determined in an aero sense it seems, but it sells.