Tested: hatch spoiler vs. vortex generators vs. stock hatch, 1996 Ford Aspire
 

I finally got around to testing and recording the effects of VGs. The test used three setups (hatch spoiler, VGs, stock hatch) in an A-A-B-B-C-C format, using the same stretches of road. The tests were done with the least amount of time possible between trials.

With spoiler:

http://www.youtube.com/watch?v=pOZ37oopc18

http://www.youtube.com/watch?v=l1INZzGQIjY


With vortex generators:

http://www.youtube.com/watch?v=pB-BAYUJ2JU

http://www.youtube.com/watch?v=1-khQEH2Gcc


Stock hatch:

http://www.youtube.com/watch?v=JDA561vytLw

http://www.youtube.com/watch?v=Kka91kS6GmI




EDIT: Here's some photos of the mods:

Spoiler:

http://i3.photobucket.com/albums/y93...e/IMG_0231.jpg

http://i3.photobucket.com/albums/y93...e/IMG_0230.jpg

http://i3.photobucket.com/albums/y93...e/IMG_0233.jpg

Vortex generators:

http://i3.photobucket.com/albums/y93...e/IMG_0087.jpg

http://i3.photobucket.com/albums/y93...e/IMG_0086.jpg

The trip strips were in place for all three runs. After each run, the tested component was removed and all else left alone. The tufts proved the strips inneffective in preventing the air from wrapping around the pillar and producing vorticies.


Testing began at 10:30 AM with 20-25 minutes between runs.


Here's an older tuft test video showing the stock hatch:

http://www.youtube.com/watch?v=wm2RPqIE8HQ


Here's a video showing attached airflow from the vortex generators:

http://www.youtube.com/watch?v=gx084gKTLZ8

Aeromodder - I'd suggest posting in a new thread.

Edit: moved.

I think you would have to make a longer run to come to a definitive conclusion, but it looks to me as though the spoiler just edges out the stock configuration and the vortex generators come in third.

The problem with VGs is that their size and placement is critical. They are not an easy fix, if at all.

Good video though, thanks for posting.

Pendragon -

I agree. The devil is in the details.

CarloSW2

Could you add a description of each setup to this thread? (Pictures please!)

Yes, please. Added as part of post 1 would be a good spot.

I'd appreciate a results summary so I don't have to watch all those videos. Thanks for doing this test!

Updated with additional pictures and videos. As for results, I can't really tell a difference between any of the setups.

Interesting, would you consider testing a setup with the VG's slightly further forward and a spoiler(bigger than stock) at the bottom of the hatch?

http://ecomodder.com/forum/attachmen...1&d=1300983772

The idea is to keep the flow attached to the bottom and there recapture the kinetic energy of the vertical component of the airflow.

Thanks for updating with pics.

Extend that spoiler into a proper Kammback, and you'll be able to detect an improvement. :)