Round vs Squarish Eggs

[Andy B]

Originally Posted by Francesca Knowles

Thanks, Andy!
But-
We're talking about basic design differences.
For this discussion, let's leave add-ons out of the equation!
The question is,
Does the Boler's design make it more "aerodynamic" than any other fiberglass trailer of the same size and dimensions?

Francesca

Lets assume we ignore the things that are mounted on the outside and we ignore the different size frontal area among the different brands, then the question is only which shape is more aerodynamic. We can also ignore propane tanks and batteries mounted up front because they are in the aerodynamic shadow of the tow vehicle. Lets also assume we ignore the underside of the trailers with all the pipes and frames shapes with poor aerodynamics.

The rounded shape has to be more aerodynamic than the square shape. The phrase "It has the aerodynamics of a brick" points out that square shaped objects do not slip through the air very well. There are no sports cars or airplanes that are square shaped. Now if you compare the shapes but not the sizes of a Boler with a Burro or an EggCamper, there may not be much difference. However comparing those more rounded campers with the square ones like a Hunter or a Play-Pac or a Companion there would be a difference.
There are brands that are somewhere in between the square and rounded because they are a square shape but with more rounded corners. Rounding the corners even a small amount can make a significant difference compared sharp corners.

The things that we are ignoring in this discussion have a greater influence on the aerodynamics than the shape does.

[Greg H]

Ah, but there is more turbulence between the Tow Vehicle and the trailer than you think. That's the reason semi trucks have that small extension at the back of the sleeper, the closer the truck is to the trailer the less air gets in there.

[Andy B]

Originally Posted by Greg H

Ah, but there is more turbulence between the Tow Vehicle and the trailer than you think. That's the reason semi trucks have that small extension at the back of the sleeper, the closer the truck is to the trailer the less air gets in there.

Francesca asked that we not include factors other than the trailer shape. I don't think it was ever said that there was no turbulence between the tow vehicle and the trailer (an aerodynamic shadow is made up of turbulence). The tow vehicle size and shape and proximity to the trailer all have effects but it is only the trailer shape that Francesca asked about.

[Francesca Knowles]

Originally Posted by melissab

With e'body watching their MPG's, I was wondering if anybody has towed both a round egg and a squarer (is that a word??) egg and can report on the MPG differences? In particular I was thinking of the Scamp/Bolers compared to the Trilliums/Escapes. I'd think the squarer FG rigs would fare worse. So is there a difference between the 2 shapes and gas mileage? And if not, why not?

Not to mention the original Poster!

Francesca

[Greg H]

Oh, now it's a shadow. Ok, back to round versus square nothing else matters. I got it. Francesca, I like round, so I'm going to say round.

[Francesca Knowles]

(heavy sigh)

Melissa inquired 65 posts ago as to whether there's any significant difference in the aerodynamic design among the most common trailers under discussion in this forum.
When it comes to gas mileage, you understand.
She names the "types".
I posted pictures of the "types".
I see very little "shape" difference among them.
I say, Melissa, if you're still with us- stay within this "group of shapes", and you'll do as well as can be expected of any large object being towed down the road.
But there isn't a spit's worth of difference within the group as far as design is concerned.
This is the OTHER situation where size matters, though, so if you expect "satisfaction" at the pumps, buy the trailer with the smallest frontal area whose interior space works for you.

Francesca

[Mike Magee]

If I were to have a testing setup and wanted to make a prediction, I would expect the more rounded eggs to outperform the less rounded eggs by perhaps 1 mpg. I base that guess largely on the fact that my Burro beat my totally-square-edged cargo trailer by 3 mpg. A difference of, say, 16 vs. 15 mpg will only yield a savings of $21 per 1000 miles traveled, assuming $5/gallon gas. It's not much.