Evo X Vortex Generator
Mar 17, 2009, 10:56 PM
#122
ok. so you put VGs on a car without a wing.. you DO understand WHY the VGs were designed in the first place... it was to keep airflow attached to the rear window longer, as to speed up air underneath a wing to create more downforce.
by removing the wing and adding VGs.. you now subsequently kept the air flow attached to the car longer.. for... no reason other that to induce more rear lift..
Mar 18, 2009, 06:54 AM
#124
Evolving Member
iTrader: (2)
Join Date: Feb 2009
Location: NJ
Posts: 216
Likes: 0
Received 0 Likes
on
0 Posts
ok. so you put VGs on a car without a wing.. you DO understand WHY the VGs were designed in the first place... it was to keep airflow attached to the rear window longer, as to speed up air underneath a wing to create more downforce.
by removing the wing and adding VGs.. you now subsequently kept the air flow attached to the car longer.. for... no reason other that to induce more rear lift..
by removing the wing and adding VGs.. you now subsequently kept the air flow attached to the car longer.. for... no reason other that to induce more rear lift..
Mar 18, 2009, 08:17 AM
#126
Cool video on VGs:http://www.youtube.com/watch?v=We8LWkqjdX4
VGs are purposeful without a wing. And wings are functional without VGs. The two can be combined to augment the efficacy of the wing, but alone the VG and rear spoiler are still functional.
Nice.
VGs don't reduce turbulence. They help prevent flow separation behind the vehicle thereby reducing drag.
More here: http://www.mitsubishi-motors.com/cor...004/16E_03.pdf
And here:http://en.wikipedia.org/wiki/Vortex_generator
The wing on the Evo X has been designed to both prevent flow separation and reduce lift (NOT increase downforce--a bit of nuance.)
More here (p.38):http://www.mitsubishi-motors.com/cor...f/2008/20e.pdf
ok. so you put VGs on a car without a wing.. you DO understand WHY the VGs were designed in the first place... it was to keep airflow attached to the rear window longer, as to speed up air underneath a wing to create more downforce.
by removing the wing and adding VGs.. you now subsequently kept the air flow attached to the car longer.. for... no reason other that to induce more rear lift..
by removing the wing and adding VGs.. you now subsequently kept the air flow attached to the car longer.. for... no reason other that to induce more rear lift..
Nice.my understanding is the vg reduces turbulence at the back of the car which still helps your car's aerodynamics with or without a wing. yes, the effect is maximized with the wing but even without it, it still smooths airflow giving the car "some" downforce, although the original intent of the vg (to be used with a wing) is now minimized without the wing. but the point is, it still functions and provides some benefit just not to its full potential without the wing.
More here: http://www.mitsubishi-motors.com/cor...004/16E_03.pdf
And here:http://en.wikipedia.org/wiki/Vortex_generator
The wing on the Evo X has been designed to both prevent flow separation and reduce lift (NOT increase downforce--a bit of nuance.)
More here (p.38):http://www.mitsubishi-motors.com/cor...f/2008/20e.pdf
Mar 18, 2009, 08:41 AM
#127
Newbie
iTrader: (1)
Join Date: Jun 2004
Location: Singapore
Posts: 71
Likes: 0
Received 0 Likes
on
0 Posts
the article is for evo 9, but would it apply to evo x?
Wouldn't it be appropriate to do aerodynamic test for it to be effective?
Wouldn't it be appropriate to do aerodynamic test for it to be effective?
Last edited by evosoh; Mar 18, 2009 at 08:46 AM.
Mar 18, 2009, 10:46 AM
#129
The article gives an overview of how VGs work. The quantitative effects of adding a VG will differ between applications (e.g. Evo 9, 10, or Corolla ), but the principles are the same.
Yes, absolutely. And if you look at that 'Cool video' from my post, it looks like there might be an easy way to qualify whether or not adding a VG yields some noticeable results.
), but the principles are the same.
Wouldn't it be appropriate to do aerodynamic test for it to be effective?
Mar 18, 2009, 06:11 PM
#130
ok. so think about a regular car shape... big hump for roof and a tapering rear window to the trunk. most sedan designs have an inherent rear lift due to airflow going over the rear of the car...this airflow over the rear, the longer it is attached, will cause a lower pressure zone and lift the rear of the car due to high speeds...
to prevent this rear lift, many designers try to "spoil" the airflow causing the air to separate sooner, reducing this lifting affect.
VGs delay flow separation. Thus keeping the flow attached longer... reason why you want VGs with a high rear wing, is because with the flow attached longer, there will be more airflow underneath a wing to make the wing more effective in providing more downforce.
take away the wing, and what do you have? you have a condition where flow will stay attached longer, causing more lift than a car w/o it.
VGs will only reduce drag at higher lift coefficients.. but at lower lift coefficients, the VGs actually increase drag.. you just need to find the correct size of VG to reduce the drag... but in a wingless configuration, if a VG induces rear lift due to reduction in flow separation, what's the point? you want the car stable at high speeds not loose.
sigh.. looks like i'll have to rely on my own string / flow tests to prove this one..
to prevent this rear lift, many designers try to "spoil" the airflow causing the air to separate sooner, reducing this lifting affect.
VGs delay flow separation. Thus keeping the flow attached longer... reason why you want VGs with a high rear wing, is because with the flow attached longer, there will be more airflow underneath a wing to make the wing more effective in providing more downforce.
take away the wing, and what do you have? you have a condition where flow will stay attached longer, causing more lift than a car w/o it.
VGs will only reduce drag at higher lift coefficients.. but at lower lift coefficients, the VGs actually increase drag.. you just need to find the correct size of VG to reduce the drag... but in a wingless configuration, if a VG induces rear lift due to reduction in flow separation, what's the point? you want the car stable at high speeds not loose.
sigh.. looks like i'll have to rely on my own string / flow tests to prove this one..
Mar 18, 2009, 07:23 PM
#131
ok. so you put VGs on a car without a wing.. you DO understand WHY the VGs were designed in the first place... it was to keep airflow attached to the rear window longer, as to speed up air underneath a wing to create more downforce.
by removing the wing and adding VGs.. you now subsequently kept the air flow attached to the car longer.. for... no reason other that to induce more rear lift..
by removing the wing and adding VGs.. you now subsequently kept the air flow attached to the car longer.. for... no reason other that to induce more rear lift..
I put it on there for the sole purpose of looks. Not because I am going for the new land speed record. But anyways thanks for your concern.
Last edited by arbo651; Mar 18, 2009 at 07:26 PM.
Mar 30, 2009, 10:58 AM
#133
Evolving Member
iTrader: (1)
Join Date: Jan 2009
Location: Palmdale, California
Posts: 236
Likes: 0
Received 0 Likes
on
0 Posts
While were on the topic of aerodynamics... My X came with the smaller wing/spoiler, anybody know just how "effective" it is or if it is at all? I want the SSS spoiler, but can't justify spending $400+ on it.
