Fuel Economy, Hypermiling, EcoModding News and Forum - EcoModder.com - View Single Post - Aerodynamic Streamlining Template: Part-C

3-Wheeler · 08-02-2015, 10:09 PM

Hi Phil,

I'm not trying to be picky, even though it could come across this way, but I do see some conflicting length/width ratios for the minimum airfoil shape posted at EcoModder.

The link below has some information that I will present below, and discuss.

http://ecomodder.com/forum/showthrea...rt-c-9287.html

The image below has sections of several minimum drag sources that show length/width ratios.

Starting from the top of the graphic, the minimum L/W ratio seems to be 2.5:1. I did not scale the graphic closely.

The second graphic shows a ratio of 1.0/.255 = 3.92 L/W

The third graphic clearly shows 2.5 L/W ratio

The C-version Streamlining Template shows a ratio of 4.72/2 = 2.36

I've looked on-line and did not find any other L/W information for subsonic winglets, and minimum drag, so this type of information may be limited to Hucho and other rare sources.

I do recall that you have mentioned that the minimum drag occurs at a L/W ratio of 2.5 many time before, yet some of the other sources do not match this, including the Streamlining Template.

Thanks, Jim.

08-02-2015, 10:09 PM	#630 (permalink)
3-Wheeler Master EcoModder Join Date: Dec 2008 Location: Southern WI Posts: 827 AlienMobile - '00 Honda Insight Team Honda 90 day: 80.05 mpg (US) Thanks: 101 Thanked 560 Times in 191 Posts	Optimum Length/Width Ratio For Minimum Drag Hi Phil, I'm not trying to be picky, even though it could come across this way, but I do see some conflicting length/width ratios for the minimum airfoil shape posted at EcoModder. The link below has some information that I will present below, and discuss. http://ecomodder.com/forum/showthrea...rt-c-9287.html The image below has sections of several minimum drag sources that show length/width ratios. Starting from the top of the graphic, the minimum L/W ratio seems to be 2.5:1. I did not scale the graphic closely. The second graphic shows a ratio of 1.0/.255 = 3.92 L/W The third graphic clearly shows 2.5 L/W ratio The C-version Streamlining Template shows a ratio of 4.72/2 = 2.36 I've looked on-line and did not find any other L/W information for subsonic winglets, and minimum drag, so this type of information may be limited to Hucho and other rare sources. I do recall that you have mentioned that the minimum drag occurs at a L/W ratio of 2.5 many time before, yet some of the other sources do not match this, including the Streamlining Template. Thanks, Jim. Attached Thumbnails __________________ Under-Belly Panels: http://ecomodder.com/forum/showthrea...els-10638.html Tail Extension: http://ecomodder.com/forum/showthrea...ect-13533.html Last edited by 3-Wheeler; 08-02-2015 at 10:19 PM..