[freebeard]

Originally Posted by aerohead

trailer gap data/ trailer drag reduction data

I ran the additions through MacOS Summarize Service to cut throguh the obfuscated punctuation:

*In 1982,the 'Trailer Dome',of Fibrelock Fabrics Ltd,of Dorset,England,demonstrated a drag reduction,from 32%-to-52%,by eliminating all but 2.8% of trailer gap, with an inflated bulbous nose on a caravan trailer.

...*Sloped-nose and V-nose trailers have deceptive drag liabilities,as beneficial stagnation bubbles of 'blunt-nosed' trailers are absent,to the detriment of both towing vehicle,but trailer as well.Hucho illustrates the lack of any drag advantage of sloped-nose trailers.Owner testimonials relate the same observations concerning V-nose trailers.

*Presently,in the world of RVs,the least offensive gap belongs to motorhomes, pulling toy haulers of smaller frontal area,such that the trailer becomes a wake rider,stuffing the wake, approximating a solid box cavity;organizing the motorhome's wake and delivering the resulting flow to a separation point of smaller cross-section and higher base pressure.

...*Online,an RV owner shared his experiment with a 2007 Toyota Tundra,pulling a Layton Skyline travel trailer.His original 8-MPG improved to 9-MPG with the addition of a full tonneau cover,then by tilting the tonneau up,as a air-deflector,fuel economy rose to an average 11.5 MPG.

...*Pat Nixon of Texas Tech, put some video together for me back in 1991,when we were doing the Becker-Lyon BMW LSR Bonneville motorcycle streamliner project.It included video of the T-T truck research,in which the fifth wheel bulbous nose did about as much good as anything the crew experimented with.A lesson not lost on Airstream,Casita,SCAMP,Happier Camper,ARGOSSY,..................

*Both BamZipPow and I are running zero-gap trailers.I'll let him tell his story over at his thread.So far,with an incomplete project,I'm sitting at delta-zero mpg pulling mine.