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Old 07-31-2021, 04:08 PM   #9 (permalink)
Hersbird
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Quote:
Originally Posted by Gschuld View Post
I understand what you are saying overall but I’m not sure if I fully agree with your first statement. If a cube and teardrop shape have equal frontal area, the teardrop shape will have significantly less drag.

Granted, the CD difference between a modern full size truck and a Jeep Grand Cherokee SRT is pretty minimal I’d think. I assume that is what you were getting at.

The airflow over a modern truck with a tonneau cover appears to leave the vehicle mostly just over the tailgate. Pulling a standing height 7’ wide cargo trailer, the airflow over his truck is running into about 30 sq ft of “new” frontal area. That has to hurt.

George
I didn't say anything about drag, I just said frontal aera. Right though you do take the frontal aera times the Cd to get overall drag. So even a small poorly shaped object may have better economy than a large optimal shaped object. The Ford and the Jeep are pretty poor on both Cd and frontal aera so that's out the window.

Anyway, when towing, it's all going to be the frontal aera of the trailer and the Cd of the trailer. I'm just saying something big and high drag in front of the trailer is going to seem less effected by the big high drag trailer.
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