08-29-2012, 04:58 PM
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#11 (permalink)
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EcoModding Apprentice
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In my opinion VG's are to be used when air flow needs to go around a curve that would normally have detached turbulent flow such as the the very back fuselage of a 737 or the aft side of an airplane wing at the flaps. They in themselves create minor drag that can be harnessed to eliminate major drag.
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08-30-2012, 08:33 AM
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#12 (permalink)
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Master EcoModder
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Quote:
Originally Posted by ChazInMT
Why are these not properly corralled?
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Because VG can work.
They won't give the claimed results regarding FE though.
Despite their tiny size, they ARE working on my A pillars and mirrors .
(noise reduction & altered water flow on side windows)
Yet I fail to see how what is essentially a half-teardrop (and even described by the manufacturer as such) would create a vortex powerful enough to have some effect.
The idea behind a VG is to create a serious vortex, hence they are normally not streamlined shapes.
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Last edited by euromodder; 08-30-2012 at 08:50 AM..
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08-30-2012, 09:15 AM
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#13 (permalink)
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Corporate imperialist
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Quote:
Originally Posted by scivicblu83
In my opinion VG's are to be used when air flow needs to go around a curve that would normally have detached turbulent flow such as the the very back fuselage of a 737 or the aft side of an airplane wing at the flaps. They in themselves create minor drag that can be harnessed to eliminate major drag.
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And this has to be done in a wind tunnel or you are likely just adding drag.
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08-30-2012, 10:45 AM
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#14 (permalink)
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Batman Junior
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The fact that the company is seeking testimonial evidence from customers interested in participating in "field trials", rather than posting quality 3rd party data says all we need to know about how effective these things are going to be for the vast majority of applications.
We know some of the MPG claims being made are so far out of the realm of possibility as to be laughable.
Also laughable:
Quote:
Oh, look, my horse has a VG on its forehead!
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I LOL'd.
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08-30-2012, 03:34 PM
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#15 (permalink)
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DieselMiser
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Quote:
Originally Posted by euromodder
Yet I fail to see how what is essentially a half-teardrop (and even described by the manufacturer as such) would create a vortex powerful enough to have some effect.
The idea behind a VG is to create a serious vortex, hence they are normally not streamlined shapes.
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Simple bumps can work like vortex generators. They don't necessarily have to create a vortex. The main thing they have to do is mix the slower moving boundary layer air with faster air to speed it up. Dimples on a golf ball do the same thing. Vortex generators are commonly used to do it because they can do it with lower drag in most cases. The best way to do the same thing without creating a vortex is a suction slot to suck away the slow boundary layer (but of course this uses energy).
Link to an example of bumps in action Pectoral fins of humpback whales inspire new flight technology
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08-30-2012, 04:40 PM
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#16 (permalink)
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I can 'buy' that as a semi-universal stick-on, one might see benefit from a zigzag at the trailing edge of necessarily truncated foils intended to invoke flow separation - like deck extension spoilers or kammbacks or side mirrors. I can also accept that under the right conditions and with exactly correct placement these gaspods can reduce drag by a tiny percent. Like many unicorns (in any industry, not only ecomodding), there's an element of plausibility if every condition is met exactly right and if a problem actually exists to address in the first place. I find it unlikely an average user can expect meaningful improvements from arbitrary placement - but I guess if it makes them feel good or if the presence of the bumps provoke conversation or thoughts about energy consumption, that can be a useful effect.
Still seems like the sort of thing the corral was meant for, unicorns are always free to grow wings and fly outta' there if they're strong enough.
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08-30-2012, 06:19 PM
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#17 (permalink)
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Batman Junior
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Quote:
Originally Posted by shovel
Still seems like the sort of thing the corral was meant for, unicorns are always free to grow wings and fly outta' there if they're strong enough.
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Well put.
Moved to the corral for now, mainly because it's better that people are skeptical of the product.
(And the countdown begins for our first non-scientific testimonial new user to sign up...)
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08-31-2012, 12:05 AM
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#18 (permalink)
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Drive less save more
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Why put them in front of the windshield on the blue wagon? they are placed right at the low pressure zone before the windshield. If any effect is wanted from them they should of been placed further ahead where the air flow is stronger for them to interact in. To be honest the hood needs a cowling to direct the air away from the windshield not to it.
On the rear VG's appear to be in the air stream with no real purpose. They are not attaching the airflow nor directing it anywhere.
They become Hood Ornaments in the wrong hands.
Its all about placement, first you have to understand how they will interact with the airflow then how you can use that to your cars benefit.
Smoke testing would be a effective way to test the effect of the placement.
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08-31-2012, 12:55 AM
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#19 (permalink)
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Request permission to move information to Aerodynamics
Quote:
Originally Posted by MetroMPG
Well put.
Moved to the corral for now, mainly because it's better that people are skeptical of the product.
(And the countdown begins for our first.... SNIP... new user to sign up...)
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and invite you to read the scientific basis before dishing the product.
[link to site removed by admin - Google Gaspods, if you like ]
Same firm that does the same modeling for BMW, Mercedes, Ford, most of the industry. And, GasPods are not vortex generators.
Request permission to have thread moved to aerodynamics.
Yes, I am President of AeroHance, makers of GasPods.
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08-31-2012, 01:08 AM
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#20 (permalink)
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Drive less save more
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Metro you are astute
Of course they are not Vortex generators.. they are gaspods and do not interact effectively with the air at all.
Only in the make believe world of your SIMULATIONS do they perform,The placement of them is laughable see my above post.
Please explain the pre windshield placement of them and the science behind it.
Also the end of the roof placement of them and the science behind it.
see the marketing video below
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Last edited by ecomodded; 08-31-2012 at 01:27 AM..
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