[gumby79]

What is the reason for the "ears"? Redirecting flow toward the boat tail?

It is part of the functional design of the standalone headache rack/ long load carrying support to prevent damage to cab from ladders and long pipe.
I made a mistake matching the silhouette of the back of a cab, wound up being too short on the corners and dead even in the center(load sitting on cab sheet metal). So I added the flat 1:24 wing (24x longer than thick =1/8"×3)with 3/16" positive camber(nose up) center 0° off horizontal, 3/8" pos. camber at the tips. The triangular supports mid-span are also set to approximately 10 to 15 degrees out of air flow travel direction ( would cause counter-rotating vortexes off of each leg of the triangle
All wings that produce lift have down wash. So yes the patch(wing) is designed to use the down wash to catch and mitigate the turbulence caused by the cab to canopy gap ( second thing the wing patch was the cab angles forward resulting in my ideal half inch at the base of a headache rack and 3.5" at the top).


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freebeard
Quote:
It demonstrates what is happening in the wheel wells very nicely. At 0:03 and 0:51
Sorta. It would be better with the wheel rotating.
Yesterday 07:43 AM

agreed spin would be better . Best would be engine running at various speeds primarily Peak torque and Peak horsepower and a moving floor treadmill, while we're at it dreaming big put that treadmill on a turntable so we can account for crosswind interaction. wind is almost never straight on so the strate up wind tunnel testing only demonstrates about 2% of real world conditions primarily the Gorge between Bonneville Dam and The Dalles