Vortex generators |
|
Porsche, and the Porsche crest are registered trademarks of Dr. Ing. h.c. F. Porsche AG.
This site is not affiliated with Porsche in any way. Its only purpose is to provide an online forum for car enthusiasts. All other trademarks are property of their respective owners. |
|
Vortex generators |
retrotech |
May 19 2006, 09:00 PM
Post
#1
|
retrotech Group: Members Posts: 470 Joined: 2-November 03 From: Mosier, Oregon Member No.: 1,302 |
Is there any new experience to report, about the effectiveness of using Vortex Generators?
|
race914 |
May 20 2006, 09:48 AM
Post
#2
|
73 914-4 Group: Members Posts: 1,006 Joined: 31-October 05 From: Nipomo, California (Central Coast) Member No.: 5,027 Region Association: Central California |
|
Joe Ricard |
May 22 2006, 11:22 AM
Post
#3
|
CUMONIWANNARACEU Group: Members Posts: 6,811 Joined: 5-January 03 From: Gautier, MS Member No.: 92 |
I am ssssoooo waiting to see if there is any difference with Air tabs.
I am just about ready to get them just for the cool factor. |
race914 |
May 22 2006, 12:04 PM
Post
#4
|
73 914-4 Group: Members Posts: 1,006 Joined: 31-October 05 From: Nipomo, California (Central Coast) Member No.: 5,027 Region Association: Central California |
For the June event I'm going to get some times with the airtabs, then switch tops with #25 and compare the times.
Without airtabs I can't stay full throttle in 5th going clockwise through the riverside turn. Rear end gets way too light and starts 'dancing'. Got my fingers crossed that the vortex generators will help get some air down to the rear spoiler! (IMG:http://www.buttonwillowraceway.com/images/race_01_config.gif) |
Joe Ricard |
May 22 2006, 01:47 PM
Post
#5
|
CUMONIWANNARACEU Group: Members Posts: 6,811 Joined: 5-January 03 From: Gautier, MS Member No.: 92 |
Man I wish I lived in Kalifornia. That is WAY bigger than NPR in Lousianna.
|
Aaron Cox |
May 23 2006, 11:15 AM
Post
#6
|
Professional Lawn Dart Group: Retired Admin Posts: 24,541 Joined: 1-February 03 From: OC Member No.: 219 Region Association: Southern California |
i saw an EVO with vortex genorators on its roof yesterday...
|
Joe Ricard |
May 23 2006, 02:11 PM
Post
#7
|
CUMONIWANNARACEU Group: Members Posts: 6,811 Joined: 5-January 03 From: Gautier, MS Member No.: 92 |
Well so much for that shit. If the ricers guys start putting them on then I will keep them off.
UNLESS someone has evidence of it really working. then I will just paint them flat black like the targa top. |
byndbad914 |
May 23 2006, 03:04 PM
Post
#8
|
shoehorn and some butter - it fits Group: Members Posts: 1,547 Joined: 23-January 06 From: Broomfield, CO Member No.: 5,463 Region Association: None |
Got my fingers crossed that the vortex generators will help get some air down to the rear spoiler! That will be interesting to see if it really can get an effect down to the spoiler. Vortex generators work best with wings, or a rear spoiler/tail section that is high enough to have the tumbling air move over them. My good friend I met in college works for Honda now, but previously worked for a couple of Indy car design places and he really knows a lot about aero, and he doesn't think it would make any difference with the spoiler with the way the rear is designed, though it may help with the overall lifting issue. I didn't really notice the lifting with my car until I was up around 130mph or so on the front stretch of Willow (I don't think you go that fast at Buttonwillow unless you remove the bus stop and go straight down the back). My car got a bit "darty" around 130 to 140-ish. I have a 6" Sheridan spoiler and was talking about adding those tabs to see what would happen and he said maybe with a spoiler that tall, but thought controlling the air under the car would be far more beneficial than the airtabs. We both agreed it was worth a try though for $30. I am adding a wing to mine, so I will be getting those tabs as well and have 2 lids, so I will tab one and leave the other stock to compare. It will be awhile for me though... my friends rented Buttonwillow this Thursday and I thought my car would be done, but I have had a one-month setback that is just killing me (IMG:style_emoticons/default/mad.gif) That would have been 8hrs with only 14 other cars, but oh well! |
Randal |
May 23 2006, 03:42 PM
Post
#9
|
Advanced Member Group: Members Posts: 4,446 Joined: 29-May 03 From: Los Altos, CA Member No.: 750 |
|
byndbad914 |
May 23 2006, 04:04 PM
Post
#10
|
shoehorn and some butter - it fits Group: Members Posts: 1,547 Joined: 23-January 06 From: Broomfield, CO Member No.: 5,463 Region Association: None |
Where do you get these babies? Here is a link that was posted elsewhere http://www.buyairtab.com/index.php?main_pa...054559679f89fc2 |
mikelsr |
May 23 2006, 08:46 PM
Post
#11
|
Senior Member Group: Members Posts: 657 Joined: 2-January 05 From: Mahomet, IL Member No.: 3,390 Region Association: Southwest Region |
A friend of mine is a retired engineering professor and we were talking about the vortex generators at one of our Porsche Saturday AM get togethers. He is very well known and respected in the engineering and PCA racing communities.
Here is what he said after I showed him a picture off the internet: "What this picture shows are a type of vortex generator but these are WAY to large! The next time you fly look out the window of the aircraft about where the engines are mounted below the wings and you will see a row ( or two ) of small one or two inch high hat appear to be tiny wings sticking out of the wing and with a small angle to the flight direction. These produce vortices which help keep the flow attached to the wing and increase lift The add-on's in the picture you sent may make the owner happy but will only increase the drag. I can't see that they will produce any help for any thing." |
DanT |
May 23 2006, 08:50 PM
Post
#12
|
Going back to the Dark Side! Group: Members Posts: 4,300 Joined: 4-October 04 From: Auburn, CA Member No.: 2,880 Region Association: None |
wow, talk about a bummer.....
That last post kind of takes all the fun out of it... (IMG:style_emoticons/default/smile.gif) |
Trekkor |
May 23 2006, 09:07 PM
Post
#13
|
I do things... Group: Members Posts: 7,809 Joined: 2-December 03 From: Napa, Ca Member No.: 1,413 Region Association: Northern California |
...Except, our cars don't go 500mph.
I'd like to see some wind tunnel pics. KT |
retrotech |
May 24 2006, 12:15 AM
Post
#14
|
retrotech Group: Members Posts: 470 Joined: 2-November 03 From: Mosier, Oregon Member No.: 1,302 |
I started this thread, because I had intended to install the Factory Mitsubishi VG. The ones you are referring to are designed for Semi's, with long straight, flat panels. As I understood, they were trying to get clean release at the rear, to lessen drag. The smaller version on Mitsu. were developed, not just eye candy. There design is to keep air attached, reducing lift, and or keeping air in the vicinity of wing/spoiler.
I still think there is potential for improved stability at speed. |
brokenmoped |
May 24 2006, 01:22 AM
Post
#15
|
Member Group: Members Posts: 143 Joined: 27-May 05 From: Mission Viejo, CA Member No.: 4,152 |
|
race914 |
May 24 2006, 09:56 AM
Post
#16
|
73 914-4 Group: Members Posts: 1,006 Joined: 31-October 05 From: Nipomo, California (Central Coast) Member No.: 5,027 Region Association: Central California |
...Except, our cars don't go 500mph. I'd like to see some wind tunnel pics. KT (IMG:style_emoticons/default/agree.gif) I'm sure the stick on airtabs wouldn't do well at 737 speeds. Not sure if the airplane devices work well at ~120mph ? (IMG:style_emoticons/default/confused24.gif) Here is the 'operational concept' from www.airtab.com (IMG:http://www.airtab.com/Images/trailflo.gif) Here is how my roof turned out Will this help get airflow to the rear spoiler? Don't know... but worth a try for $27.50. The with & without laptimes will tell the story! I'll post back after our June BW event. |
byndbad914 |
May 24 2006, 07:20 PM
Post
#17
|
shoehorn and some butter - it fits Group: Members Posts: 1,547 Joined: 23-January 06 From: Broomfield, CO Member No.: 5,463 Region Association: None |
I'm sure the stick on airtabs wouldn't do well at 737 speeds. Not sure if the airplane devices work well at ~120mph ? (IMG:style_emoticons/default/confused24.gif) Here is the 'operational concept' from www.airtab.com Will this help get airflow to the rear spoiler? Don't know... but worth a try for $27.50. The with & without laptimes will tell the story! I'll post back after our June BW event. I am very interested to see what you determine! I think the best way to know how well these work for you is if you can get up to high mph in a sweeper turn. BW only has one and it isn't really that long (not like T7 thru T8 at Willow Springs). If you get better rearend grip and can get a higher mph thru a sweeper, then those tabs are working. To clarify - if the car wants to oversteer at 105mph without the tabs, but you can run through at 105 or faster without oversteer with the tabs, then they are working. I agree there will definitely be more drag with their size. The issue always exists with anything aero - how much drag can you handle v. increase to handling performance (though on a smaller degree with smaller generators). If you have the HP to pull the generators through the air, and they help you go faster, the driving benefit outweighed the drag cost. Getting the air to tumble over the rear section of the car may just be enough to reduce the crazy lift the car creates otherwise. I will gladly pull them through the air to get that benefit. Hard to say without a wind tunnel (which who has one of those (IMG:style_emoticons/default/blink.gif) ) or just some good old fashioned testing. BTW, if you have a full scale wind tunnel in the SoCal area, you are my new best friend!! Probably have a whole new club of best friends (IMG:style_emoticons/default/biggrin.gif) Speeds below 100mph are probably worthless as the car doesn't experience a bunch of lift at the rear anyway. Hard to hit speeds much above 100mph at BW though, just through the bus stop and the sweeper after it. But they go by so fast... BEST OF LUCK - if they work a lot of us will benefit on the larger tracks like Willow Springs! (IMG:style_emoticons/default/driving.gif) |
Trekkor |
May 24 2006, 10:16 PM
Post
#18
|
I do things... Group: Members Posts: 7,809 Joined: 2-December 03 From: Napa, Ca Member No.: 1,413 Region Association: Northern California |
|
brant |
May 25 2006, 07:55 AM
Post
#19
|
914 Wizard Group: Members Posts: 11,824 Joined: 30-December 02 From: Colorado Member No.: 47 Region Association: Rocky Mountains |
numbers will tell.
all else is conjecture. |
sww914 |
Jun 12 2006, 11:30 PM
Post
#20
|
Advanced Member Group: Members Posts: 2,439 Joined: 4-June 06 Member No.: 6,146 Region Association: None |
They're cute!
|
Lo-Fi Version | Time is now: 27th December 2024 - 01:30 AM |
All rights reserved 914World.com © since 2002 |
914World.com is the fastest growing online 914 community! We have it all, classifieds, events, forums, vendors, parts, autocross, racing, technical articles, events calendar, newsletter, restoration, gallery, archives, history and more for your Porsche 914 ... |