"Vortekz" generators....opinions??
 

https://www.vortekz.com/

I just ran across these while doing a Google search. Thier theory appears to be sound(...on the surface, anyway) and the price is nice as well.

So, whadyathink?

disclaimer: I am in no way affiliated with this particular company nor do I advocate the advancement of "snake oil" products. I simply want some feedback and/or speculation about this product from the experienced & educated people here.:thumbup: :)

Seems to be the same thing as Air Tabs, which might help since your Volvo is almost as boxy as the Jeep.

Hmmm. With, admittedly, no aerodynamic knowledge involved on my part, my initial reaction is, I like them better than the airtabs or homemade sheet metal VGs. I like that they specify the angles for attachment, though they seem to have based that on someone else's research and not conducted their own windtunnel testing. Still, good price for a stick on aero-mod. I would be tempted to try a set.

Actually, I'm not really considering them for installation on my Volvo wagon. The back end of the car is beyond improvement of laminar separation...its probably more like laminar chaos. ;)
Besides, I think I'd have to mount them only inches away from my rear lip spoiler, which could possibly negate the effects of the fins & the spoiler.

Does anyone know of any tests done VGs? I'd be interested to ee the gains. Not bad for $20 though

VG tests were supposed to be my job this year - I have had a full set of Airtabs sitting in a box since late last fall. But I haven't done any testing at all in 07 (too many projects). Not saying I won't be doing it, just not sure when.

EDIT: you can find all kinds of anecdotal "evidence" about VGs on cars all over the web, but that doesn't count, IMO.

Yeah, I was hoping someone would have some good evidence. To prove or disprove. I guess it would be hard for it to actually hurt FE, but if it only improved a miniscule amount I wouldn't throw down the money. I'll search around some more but I didn't see anything.

SL8Brick -

These look cooler than the air tabs. They are on Mitsubishi Evo's. 20 bucks for 10 is a deal. I've actually been waiting for something like this.

I like how it has good instructions for installation :

https://www.vortekz.com/generators.htm#ins

I am thinking I could just get the black ones, no problemo.

CarloSW2

Considering they are probably identical to the VGs on the Mitsubishi Evo and the stuff (images, numbers) they have on their site is from Mitsubishi's research, which can be found in pdf form quite easily, I'd say they probably work quite well.

However, I spent a mere $4 for all 8 of my VGs, which are made out of a plastic butter tray I picked up at Target and cut to pieces with a hobby knife and stuck on with 3m double-side adhesive... They are modeled after the VGs on the Cessna 182 a friend of mine owns and just based on watching the dew dry off my back window, in triangular patterns extending from the positions that my VGs are placed on, I'd say they work. I will probably be tuft-testing to see in better detail the effect they have soon.

Blue03Civic -

Cool. Do you have pictures of your handiwork? Do you mean these kind of VGs? :

Attachment 775

Also, is the butter tray compatible with Parkay and/or Margarine ;) ?

CarloSW2

This topic comes up regularly. A good thread is here:
Vortex Generators / Hmmm Airtabs

Probably it comes up because nobody has properly documented results, so it remains open for speculation.

The closest thing to experimental evidence I've seen for the application I'd consider (around the trailing edge of the car) is in the pressure tests illustrated in this post:

https://www.gassavers.org/showthread....dson#post22178

I'm not buying anything spelled like that. :-)

From the look of the images above and a few more aircraft ones I saw online, the VGs were always at the beginning, unlike the car image on the Vortekz site where it's at the very end. I have a fairly boxy wagon, and would probably try this out sometime. I should really find out if my freakin air dam does anything before I test something new though :D

Nah, don't let testing get in the way of trying other stuff... :-)

I need to finish the boat tail and test that. I really want to just skip the air dam test and just finish the boat tail. It's got to have a much larger effect.

https://www.gassavers.org/attachment....1&d=1185424999

Just look at that beautiful lack of seperation I expect! Top car is original image from a study, middle car is the shape of my car, bottom car is how I hope the air flows around my boat tail. I made those spiffy images in MSPaint too!

theclencher -

Ooooooh, here's another observation/opinion. For the Evo, there seems to be an assumption that the VGs work *with* the monster Evo spoiler. This design rule would apply to coupe/sedans, not wagons.

CarloSW2

i think cfg83's right
there seems to be a lot of misconseptions on what VG's do and where they should be placed.

if we look at airplanes where they are frequently used we can conclude they work. but al they do is delay laminar flow sepparation. at the end of a vehicle there's going to be flow sepparation anyway. their funtion to have more air follow the path of the rear window, and by the spoiler.

i think on a car they might also work when attached at the top of the front window to pervent a sepparation bubble to form, on older cars especially the angle from the windshield and the root was to steep for the air to follow. althought is would make a very impractical placement of the vg's

i think vg's could work on any car is they're placed and designed correctly. but this is difficuly without any propper airflow visualisation.

Yes, as a matter of fact, I have these pictures.
https://aycu38.webshots.com/image/242...2821607_rs.jpg

https://aycu06.webshots.com/image/233...9827658_rs.jpg
Dimensions are 1" high x 1" long
https://aycu33.webshots.com/image/244...4242620_rs.jpg

So, as you can see, they are modeled after VGs like the ones in the image you posted.

And also, I think this butter tray is compatible with all makes and models of stick-type butter and margarines :D

Aha. So one could also use extruded aluminum angle stock. Probably more work though. And maybe not compatible with margarine.

More seriously, for the rear edges of a wagon, do our aero geeks think these are better than a small spoiler - that is, better than an extension of the roofline or the side panel that would extend rearward a few inches? I'd consider building one that angles downward somewhat for a mini Kamm effect. Similar spoilers on the side edges could angle inwards, same concept.

Or maybe vortex generators instead? Or vg's in addition to a slightly angled spoiler?

Honestly, though you probably already know this, a boxy wagon is pretty much aerodynamically hopeless. There is no substitute for a boat tail on a wagon but VGs, in theory, are better than a small extension (small as in 6-8"). VGs create an aerodynamic simulation of a boat tail by energizing air flow, which delays the inevitable forming of turbulence and a resulting low-pressure area. Of course, unless you have them framing your roof and side panels they won't do much good. Ideally to compliment your roof and side panel VGs a smooth body pan and floor-mounted VGs would probably help a great deal.

Of course, you could use both the extension and the VGs, which would be even better than just one, as it would provide a little more space laminar flow and probably aid in the simulated flow attachment.

Here's a rough MS B&W paint illustration of what I'm talking about.
https://aycu16.webshots.com/image/230...2626130_rs.jpg

Thanks. This confirms my suspicions re. rear end aero improvements.

True, rear-drive Volvos are nicknamed bricks for good reasons. But I seem to be making progress on it. I've built a front air dam reaching to 7" from ground level, and belly pan from air dam reaching back about 26" to approx the front axles line. With tires at about 40 psi, I get a pretty decent glide out of it now.

The whole time I've been reading about these VGs....and I've been wondering: Why hasn't anyone put these on the bottom of the car?? Attach them to the belly pan...even the bottom of the airdam. From what I understand, it should help the airflow smooth out and "skip" over parts of the rough underbelly of the car.

Raccoonjoe,
I saw an image on this site once of someone that had VGs on the underbelly pan. I can't remember who, hopefully they read this and post that picture.

Raccoonjoe, I remember someone talking about doing it once, or actually doing it, but I don't remember where I saw it. Without a full body pan, I don't think VGs will help much, unless you have a very smooth underbody on your car because the vortex they create is just going to wind up running into something under the car and being destroyed.

I remember seeing the pics also. Probably here somewhere but I have CRS syndrome (can't remember ****). Basjoos maybe? Or maybe tjts1?

Hi, it was me. Here is the thread.
https://www.gassavers.org/showthread....ight=undertray
They were, as someone said, intended to try to keep the flow a little organized and help it "skip over" the rough spots under the car.

Did they help? I do not know.

I have put on a full belly pan (except for the exhaust) and rear undertray, so I am thinking about taking the VGs off, since the underside is mostly shmooooth coroplast.

Remember that when you put VGs on, you need to orient them according to the air flow, not the body lines of the car. So you might need to do some tests to see what the actual air flow direction is. That is why the outboard VGs on the Evo are "straight" instead of "angled".

Exactly, Blue03Civic...which is why I wrote this earlier:

But, if you believe anything about the marketing materials for VGs, then you believe that they are great for boxy vehicles. At least that seems to be airtabs biggest focus...

My "Vortekz" experience....
 

Just a brief review/update......

Out of total curiousity, I did order a set of primed Vortekz generators even though I had no plans of installing them on either my Volvo or my Wife's VW Golf. One of my co-workers was curious as well, so I decided to make the $26.37 investment(freight inclusive).
They arrived only 2 days after I ordered them. The included instructions/templates are identical to the info provided on the website. The delta fins themselves appear to be well made...free of any mold lines or casting burrs. The plastic is very flexible, so a flex agent is required if you decide to have them painted. The 3M adhesive pads are custom-cut to the fin base shape and fit perfectly. Overall, I was rather impressed with the quality of materials.

Ok, so now you may be asking yourself " So, SL8Brick...what did you do with them since you didn't install them on your own car?" Well, it was my 18yr old nephew's birthday a few weeks ago. He drives a 1986 Chevy Camaro IROC thats seen better days and he's at that age where "boy racer" toys are still enticing. I sent the "Vortekz" fins to a local body shop and had them painted Chevy 'Flame Red', the same color as his Camaro. I finally installed the fins on his car last weekend. The included installation templates worked as advertised. Perhaps the most difficult part of the install was establishing a 'center line' on the roof. The T-tops on the Camaro made this quite easy, but I could see how it could become more labor intensive on a large, smooth roof with no point of reference. I had all 10 fins installed at the specified angles within an hour. They look unique on the Camaro and my nephew was pleased....whether or not they'll actually function on a fastback is beyond me.

SL8Brick

Your nephew is now going to get 50 mpg at the traffic light drag strip! :D

Seriously, thanks for the report. It's good to have the information.

Should help remove dew on the rear window more quickly, if nothing else.