Teardrops n Tiny Travel Trailers

ANDREW (actually, anyone): What do you think of the AirLiner shape, aerodynamically speaking?

A square back would make for easy entry to the kitchen area (still using a typcial t/d layout), and a double door and roof extension would give sun and weather protection if opened at a 90 degree angle.. kind of a 'walk-in' kitchen area..

Arne wrote:ANDREW (actually, anyone): What do you think of the AirLiner shape, aerodynamically speaking?

A square back would make for easy entry to the kitchen area (still using a typcial t/d layout), and a double door and roof extension would give sun and weather protection if opened at a 90 degree angle.. kind of a 'walk-in' kitchen area..

Andrew,

Sounds like you ought to put some of your aero-dynamic thoughts on one of your pages over there in your design library!!!

Mike...

Sounds like a good idea to me !!!

How many teardrop trucks have you seen .... with the sloped rear??? Now how many have you seen with that rounded deflector in front of the trailer box...??? Traditional TD rear shape may be more aerodynamic by joining the flow , but aft of the CoL on the shape turbulates and detaches anyway ... like an airfoil ...I also design planes [url] www.FoamFly.com/gallery/Glen [url]

Sorry, Arne, I read this late at night and forgot to answer the next day.

Aerodynamics of road vehicles is a tricky subject - I know just enough to know that I know little. So, with that caveat.....

I don't think the Airliner would be any worse than a conventional teardrop of the same size and it may be better (lower drag).

A few, limited aero thoughts on teardrops and similar-sized trailers:

- A teardrop sits (wholly or partly) in the wake of the tow vehicle. Design features suitable for cars/trucks may not be at all relevant to teardrops. The 'best' design of a teardrop will only be best for one particular tow vehicle.

- Drag is made up of cross-sectional area (roughly, width x height) times drag coefficient. Getting a good drag coefficient isn't easy, so reducing the cross-sectional area is the easiest way to cut drag.

- Even more important than overall cross-sectional area of the trailer is any cross-sectional area that sticks out past the tow vehicle - eliminate this if at all possible. This includes area sticking below the bottom of the tow vehicle - do not lower a teardrop if its bottom will then be below the bottom of a truck towing it. Small trailer wheels/tires will have less drag than large trailer wheels/tires - don't fit wheels any larger than your ego requires...... If you can make your trailer fit 3-6" inside the tow vehicle's cross-section (top, bottom and both sides), that will probably be even better than being the same width/height, etc.

- Length is free - a longer trailer won't have any more drag than a shorter one (at least to a first order of magnitude). However, it will be heavier!

- The traditional teardrop shape is simply styling. It is not a low drag shape, either as a trailer or as a solo vehicle. The rounded top front may do some good if the tow vehicle is fairly low, but that sloping back end is absolutely useless at cutting drag - it is there to look racy, according to 1930s fashion.

Lecture over - there will be a test on this tomorrow.

Andrew

Andrew, very interesting, thank you. I won't be so concerned about my trailer not be as low as I would like any more... Shirley and the dog will just have to learn to jump up to get in....(don't tell Shirley I said that)....

the wind beneath my wings...