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freebeard · 12-17-2015, 02:19 AM

I don't get that last bit, at all. The closest analog I can think of is the Air Curtain BMW, Ford and other use on the front wheel wells.

I suspect you will just move the separation from the top behind the edge to the throat of your converging duct. Suppose you replace the quarter-circular canard with a flat, horizontal plate to maximize the air ingested. Or just trim the curved one back. It need only protrude forward a little more than the half-round.

Edit: OTOH there're also the 'turning vanes' on the front corners of European trucks. They accept the air at right angles to the ambient flow.

With 13 posts in 3 years I'm not sure how much you've seen of the subforum.

http://ecomodder.com/forum/showthread.php/virtual-boat-tailing-30594.html"]http://ecomodder.com/forum/showthrea...ing-30594.html

Check out the PDF in the first post, figure 8, page 12. To get the effect you're hoping for they were adding extra engines. Not saying it can't be done passively, but the scale may be different than what you propose. Ford's air curtain slots are pretty small.

What about this?

Here's is MB using what I would characterize as a 'perforated Gurney flap' to reduce buffeting in an open convertible. It seems to work. What might that do at the leading edge of a long body. It would slow the air down instead of speeding it up.

Also, Australian sun visors.

http://blog.bbt4vw.com/category/stock-parts/page/9/

I like perforated plates. Flowing air will see a surface, but stagnant air can pass right thorough.

12-17-2015, 02:19 AM	#6 (permalink)
freebeard Master EcoModder Join Date: Aug 2012 Location: northwest of normal Posts: 28,734 Thanks: 8,157 Thanked 8,938 Times in 7,380 Posts	I don't get that last bit, at all. The closest analog I can think of is the Air Curtain BMW, Ford and other use on the front wheel wells. I suspect you will just move the separation from the top behind the edge to the throat of your converging duct. Suppose you replace the quarter-circular canard with a flat, horizontal plate to maximize the air ingested. Or just trim the curved one back. It need only protrude forward a little more than the half-round. Edit: OTOH there're also the 'turning vanes' on the front corners of European trucks. They accept the air at right angles to the ambient flow. With 13 posts in 3 years I'm not sure how much you've seen of the subforum. http://ecomodder.com/forum/showthread.php/virtual-boat-tailing-30594.html"]http://ecomodder.com/forum/showthrea...ing-30594.html Check out the PDF in the first post, figure 8, page 12. To get the effect you're hoping for they were adding extra engines. Not saying it can't be done passively, but the scale may be different than what you propose. Ford's air curtain slots are pretty small. What about this? Here's is MB using what I would characterize as a 'perforated Gurney flap' to reduce buffeting in an open convertible. It seems to work. What might that do at the leading edge of a long body. It would slow the air down instead of speeding it up. Also, Australian sun visors. http://blog.bbt4vw.com/category/stock-parts/page/9/ I like perforated plates. Flowing air will see a surface, but stagnant air can pass right thorough. Last edited by freebeard; 12-17-2015 at 03:45 AM..