MPG = Air Resistance vs Speed vs Weight
Improving MPG had me wondering, so I found a definitive calculator to make the math easier. http://ecomodder.com/forum/tool-aero-rolling-resistance.php Vehicle weight [1]: 10,000lb (TV & TT) Crr ...
Forum Discussion
Wind deflectors work somewhat, but they have to mounted as close to the trailer as possible and they have to be tuned correctly for the trailer. Most people aren't successful because of the A frame. Most A frames on TT's end up placing the trailer so far behind the vehicle that the wind deflector becomes useless. The air gets directed over the deflector, but quickly falls into the void between the vehicle and trailer.
Wind deflectors only address one direction of wind though, the flow over the trailer. There's still tons of air that rushes into the void from the sides and underneath the vehicle. Some of the airflow that passes over deflector actually falls off into the void as well. This all creates a very turbulent airflow which creates drag. If you could reduce how much air enters this area with a boot or fairings like the big trucks, then you would see a pretty good improvement. Then there's the whole issue with the back of the trailer.
Wind deflectors only address one direction of wind though, the flow over the trailer. There's still tons of air that rushes into the void from the sides and underneath the vehicle. Some of the airflow that passes over deflector actually falls off into the void as well. This all creates a very turbulent airflow which creates drag. If you could reduce how much air enters this area with a boot or fairings like the big trucks, then you would see a pretty good improvement. Then there's the whole issue with the back of the trailer.
