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gumby79 · 07-22-2016, 07:24 PM

The A&P book I read said
VGs (Vortex Generator) are for maintaining attached airflow at excessive angle of attack preventing a stall.
Also that a VG should be placed 1/3 cord for of the point of separation. At 15° off of the direction of airflow (as apposed to direction of travel this could be 90°to the direction of travel.
The other day I saw a 53' reafer with a VG kit (1 pice per side with ~ 12 VG each) placed ~12-18 forward of the door hinges. The oddity was the VG s were orientated wide side leading like a NACA duct intake.(>--).. I think someone didn't read the instructions and installed the left pice on th right side .

----
VGs could be used to allow a steeper angle >12° on a camback/ aerocap (as in a short bed) with out requiring the cap to be truncated . The reasons given by other builders of aerocaps for a truncated cap was . To get down to the tailgate ment an angle too steep and would cause a loss of attached air flow . With some $500/hr wind tunnel time a 3' aerocap with VG is possable . As it stands now without VG s an 8'+ bed is needed to maintain the templates <12° change of surface angle for attached flow.
Gumby Stay Flexible

07-22-2016, 07:24 PM	#18 (permalink)
gumby79 Master EcoModder Join Date: Dec 2014 Location: Butte, Montana Posts: 726 little jona - '91 Dodge D 250 first gen cummins LE Team Streamliner 90 day: 23.4 mpg (US) Little Jona airo modded - '91 Dodge RAM 3/4 TON D 250 2×4 AUTO Pickups Team Cummins 90 day: 18.5 mpg (US) The Salted Hound Jenny. - '87 Dodge Ram 50/D-50 5sp 4X4 90 day: 20.24 mpg (US) Jona Allison aero - '91 Dodge Ram D-250 Le 90 day: 20.76 mpg (US) Thanks: 208 Thanked 428 Times in 279 Posts	The A&P book I read said VGs (Vortex Generator) are for maintaining attached airflow at excessive angle of attack preventing a stall. Also that a VG should be placed 1/3 cord for of the point of separation. At 15° off of the direction of airflow (as apposed to direction of travel this could be 90°to the direction of travel. The other day I saw a 53' reafer with a VG kit (1 pice per side with ~ 12 VG each) placed ~12-18 forward of the door hinges. The oddity was the VG s were orientated wide side leading like a NACA duct intake.(>--).. I think someone didn't read the instructions and installed the left pice on th right side . ---- VGs could be used to allow a steeper angle >12° on a camback/ aerocap (as in a short bed) with out requiring the cap to be truncated . The reasons given by other builders of aerocaps for a truncated cap was . To get down to the tailgate ment an angle too steep and would cause a loss of attached air flow . With some $500/hr wind tunnel time a 3' aerocap with VG is possable . As it stands now without VG s an 8'+ bed is needed to maintain the templates <12° change of surface angle for attached flow. Gumby Stay Flexible __________________ 1st gen cummins 91.5 dodge d250 ,HX35W/12/6 QSV ehxsost manafulld wrap, Aero Tonto best tank: distance 649gps mi 24.04 mpg 27.011usg Best mpg : 31.32mpg 100mi 3.193 USG 5/2/20 Former '83 GMC S-15 Jimmy 2door 2wd O/D auto 3.73R&P '79 Chevy K20 4X4 350ci 400hp msd custom th400 /np205. 7.5-new 14mpg modded befor modding was a thing 87' Hyundai Excel 83 ranger w/87 2.9 L FI2wd auto 18mpg on the floor 04 Mitsubishi Gallant 2.4L auto 26mpg 06 Subaru Forrester XT(WRX PACKAGE) MT AWD Turbocharged 18 plying dirty best of 26mpg@70mph 95Chevy Blazer 4x4 auto 14-18mpg 04 Chevy Blazer 4x4 auto 16-22mpg