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freebeard · 02-15-2018, 03:05 PM

I don't really know. I've been offering counter-examples for consideration. It would take hours in a wind tunnel to separate fact from fantasy.

Given your departure angle requirement, retractable skegs sounds reasonable to me. They could have a polyurethane skateboard wheel at the tip. Sort of wide-spaced wheelie bars with fill panels. They could be shorter than the tail overall, or canted like on a 1961 Oldsmobile.

An important consideration would be a smooth transition from the Prius proper onto the added structure of the boat tail. I haven't done a complete boat tail myself, but the 1:1 scale study I did was to find the point of transition. It turns out on the Beetle with a Tropfenwagen tail, it's a V- or U-shape across the roof instead of a straight line. Instead of cardboard, I used 1/4" Redwood benderboard ripped in half. This could be extended to a wooden-canoe-like construction.

edit:
Looking for something else I found this old thread, A paper on aft-end underbody diffusers, and a Summary at Permalink #13.

02-15-2018, 03:05 PM	#46 (permalink)
freebeard Master EcoModder Join Date: Aug 2012 Location: northwest of normal Posts: 28,938 Thanks: 8,215 Thanked 8,987 Times in 7,424 Posts	I don't really know. I've been offering counter-examples for consideration. It would take hours in a wind tunnel to separate fact from fantasy. Given your departure angle requirement, retractable skegs sounds reasonable to me. They could have a polyurethane skateboard wheel at the tip. Sort of wide-spaced wheelie bars with fill panels. They could be shorter than the tail overall, or canted like on a 1961 Oldsmobile. An important consideration would be a smooth transition from the Prius proper onto the added structure of the boat tail. I haven't done a complete boat tail myself, but the 1:1 scale study I did was to find the point of transition. It turns out on the Beetle with a Tropfenwagen tail, it's a V- or U-shape across the roof instead of a straight line. Instead of cardboard, I used 1/4" Redwood benderboard ripped in half. This could be extended to a wooden-canoe-like construction. edit: Looking for something else I found this old thread, A paper on aft-end underbody diffusers, and a Summary at Permalink #13. __________________ . .Without freedom of speech we wouldn't know who all the idiots are. -- anonymous poster ________________ . .Because much of what is in the published literature is nonsense, and much of what isn’t nonsense is not in the scientific literature. -- Sabine Hossenfelder Last edited by freebeard; 02-15-2018 at 03:44 PM..