Notices
Aerodynamics Splitters, spoilers, and all the aero advice you can handle.
Sponsored by:
Sponsored by:

Aerodynamic Discussion Thread

Thread Tools
 
Search this Thread
 
Old Mar 12, 2013 | 08:41 PM
  #121  
Leafy's Avatar
Elite Member
iTrader: (1)
 
Joined: Jun 2012
Posts: 9,491
Total Cats: 105
From: NH
Default

Originally Posted by cordycord
Did not think of that! Is that something your typical metal finishing shop can accomplish, or can you recommend someone specific?
I would think it could end up being cheaper to just make new hubs. I've been in a booth during both plasma and thermal spray (you would thermal spray that chromium). The equipment draws a lot of juice and costs a fortune, the safety booth is real expensive and takes up a lot of room. Its cool to be in there during it for about 2 minutes and after that you want to GTFO, its hot, bright, loud, filled with toxic particles in the air, and otherwise terrible. I would think if a small shop had a setup to do it it would cost a small fortune.
Old Mar 12, 2013 | 08:44 PM
  #122  
cordycord's Avatar
Elite Member
iTrader: (2)
 
Joined: Dec 2011
Posts: 3,398
Total Cats: 560
From: SoCal
Default

Originally Posted by plucas
Just out of curiosity, but who are you using to run cfd on your car?
As soon as the details have been worked out, I'll let the cat out of the bag.
Old Mar 12, 2013 | 11:13 PM
  #123  
cordycord's Avatar
Elite Member
iTrader: (2)
 
Joined: Dec 2011
Posts: 3,398
Total Cats: 560
From: SoCal
Default

Originally Posted by Leafy
I would think it could end up being cheaper to just make new hubs. I've been in a booth during both plasma and thermal spray (you would thermal spray that chromium). The equipment draws a lot of juice and costs a fortune, the safety booth is real expensive and takes up a lot of room. Its cool to be in there during it for about 2 minutes and after that you want to GTFO, its hot, bright, loud, filled with toxic particles in the air, and otherwise terrible. I would think if a small shop had a setup to do it it would cost a small fortune.
Then local plasma spray is probably out. You can't sneeze in California without getting approval from the California Coastal Commission, CARB, and a dozen other agencies. Any legacy companies that work with Haz-Mat are hounded mercilessly. It's not like we need the jobs in this state.
Old Mar 13, 2013 | 05:17 PM
  #124  
Batou's Avatar
Newb
iTrader: (2)
 
Joined: Nov 2008
Posts: 25
Total Cats: 4
Default

Have you guys seen this blog before? I stumbled upon it, while looking for a stock miata's drag coefficient.

Splitter or Air Dam – Which Design is Best? | Hancha Blog

Looks like a good bit of info.

Name:  cfd_model_zps5ad19e37.png
Views: 1206
Size:  394.3 KB

Name:  cfd_data_zps0ebf2c6a.png
Views: 1116
Size:  130.7 KB

Name:  cfd_xz-plane_velocity_plot_zpsc3a097e4.png
Views: 1367
Size:  421.3 KB
Old Mar 13, 2013 | 05:23 PM
  #125  
thenuge26's Avatar
Elite Member
iTrader: (2)
 
Joined: Aug 2012
Posts: 3,267
Total Cats: 239
From: Indianapolis
Default

REPOST

It's technically not the same thread, but this thread was split off from the splitter height thread.
Old Mar 13, 2013 | 05:47 PM
  #126  
plucas's Avatar
Junior Member
 
Joined: Dec 2012
Posts: 74
Total Cats: 45
From: Indianapolis
Default

Originally Posted by Batou
Have you guys seen this blog before? I stumbled upon it, while looking for a stock miata's drag coefficient.

Splitter or Air Dam – Which Design is Best? | Hancha Blog

Looks like a good bit of info.

pics galore

That is my and my business partners blog. He is the suspension guy while I do aerodynamics
Old Mar 13, 2013 | 06:38 PM
  #127  
Batou's Avatar
Newb
iTrader: (2)
 
Joined: Nov 2008
Posts: 25
Total Cats: 4
Default

Sweet, I hadn't seen it before. Awesome blog! Pardon the repost.
Old Mar 13, 2013 | 08:20 PM
  #128  
triple88a's Avatar
Elite Member
iTrader: (2)
 
Joined: Apr 2006
Posts: 10,522
Total Cats: 1,830
From: Chicago, IL
Default

Originally Posted by cordycord
Did not think of that! Is that something your typical metal finishing shop can accomplish, or can you recommend someone specific?

We used to use a different shop to build up chrome and then we'd grind it on our normal machines. The shop was specifically for chrome and other coatings so it ended up being cheaper than buying our own for the amount of work we did with it. No offence but i call BS on the chrome being a fortune to run. Chroming a spindle takes about 2000 watts (160ish amps at 12 volts) for about 3 minutes. Relative that's the same as running an average microwave for 5 minutes.
Old Mar 14, 2013 | 08:45 AM
  #129  
Leafy's Avatar
Elite Member
iTrader: (1)
 
Joined: Jun 2012
Posts: 9,491
Total Cats: 105
From: NH
Default

Originally Posted by triple88a
We used to use a different shop to build up chrome and then we'd grind it on our normal machines. The shop was specifically for chrome and other coatings so it ended up being cheaper than buying our own for the amount of work we did with it. No offence but i call BS on the chrome being a fortune to run. Chroming a spindle takes about 2000 watts (160ish amps at 12 volts) for about 3 minutes. Relative that's the same as running an average microwave for 5 minutes.
I'm only speculating on the electricity, the machine here plugs into a 600 volt 4 phase plug, so it must use some serious juice. There's still a ton of overhead and up front cost.
Old Mar 14, 2013 | 09:13 AM
  #130  
triple88a's Avatar
Elite Member
iTrader: (2)
 
Joined: Apr 2006
Posts: 10,522
Total Cats: 1,830
From: Chicago, IL
Default

Originally Posted by Leafy
I'm only speculating on the electricity, the machine here plugs into a 600 volt 4 phase plug, so it must use some serious juice. There's still a ton of overhead and up front cost.
The machine i worked with in our shop ran similar setup however was a 12 volt system dc converter. It would run up to 900 amps at 14 volts (dc) for pieces that were 26" long by 5" in diameter which is about the max we did.

Correct theres high up front cost however thats something the shop has to swallow. If they want business they cant skyrocket prices when the dude next door does it for much less.
Old Mar 27, 2013 | 07:13 PM
  #131  
mx5autoxer's Avatar
Senior Member
iTrader: (1)
 
Joined: Dec 2008
Posts: 1,242
Total Cats: 57
From: Manassas, Virginia
Default

So how much does doing this help? If little, then would it be worth it if it was more aggressive with a larger opening?

Attached Thumbnails Aerodynamic Discussion Thread-dsc_1193.jpg  
Old Mar 28, 2013 | 12:24 AM
  #132  
ThePass's Avatar
Supporting Vendor
iTrader: (3)
 
Joined: Jul 2006
Posts: 3,310
Total Cats: 1,236
From: San Diego
Default

Originally Posted by mx5autoxer
So how much does doing this help? If little, then would it be worth it if it was more aggressive with a larger opening?
I did that a couple years ago when I started messing around with aero. It's one of those things that is never going to create a difference that is noticeable by the seat of the pants, but many little aero improvements can make a big difference when done properly. As a broad statement, venting the front wheel well is generally beneficial. The size of that opening there is probably just on the small side of being effective IMO. Would bigger/more aggressive be better? I think so. Hence my later version:



I'm always interested in what other have to say on these topics though!
Attached Thumbnails Aerodynamic Discussion Thread-img_5144_zpsfe1f5e54.jpg  
__________________
Ryan Passey
Old Mar 28, 2013 | 03:45 AM
  #133  
mx5-kiwi's Avatar
Senior Member
 
Joined: Dec 2010
Posts: 993
Total Cats: 57
From: Auckland, NZ
Default

I have nothing to add v effectiveness but that small opening looks really good!!

Are there any pictures of the whole car?

In saying that, the idea is to relieve air pressure created by the wheel / tyre spinning so even a small hole must help considerably........I would have thought it would releive more pressure than the louvered vents Le Mans type cars use on the top of the fenders.....

But then the louvres in the fenders are placed in the correct position (If i remember my reading of the Engineer to Win etc series of books, read many years ago...)
Old Mar 28, 2013 | 10:11 AM
  #134  
mx5autoxer's Avatar
Senior Member
iTrader: (1)
 
Joined: Dec 2008
Posts: 1,242
Total Cats: 57
From: Manassas, Virginia
Default

Ah good. I was hoping you'd reply, Pass. Is there any situation where it would be negative? For instance is it better for a track with a lot of high speed corners or a track with long straights?
Old Mar 28, 2013 | 01:33 PM
  #135  
ericwh's Avatar
Junior Member
iTrader: (1)
 
Joined: Feb 2012
Posts: 140
Total Cats: 2
From: Hagerstown, MD
Default

Originally Posted by mx5-kiwi
Are there any pictures of the whole car?
There's a few floating around: My NA becomes a track car (Build thread) - ClubRoadster.net
Old Mar 28, 2013 | 01:39 PM
  #136  
1993ka24det's Avatar
Thread Starter
Senior Member
 
Joined: Oct 2011
Posts: 646
Total Cats: 62
From: The Race Track & St Pete FL
Default

This is something I'm working on and hopefully this weekend if I'm still not to sick I will get a big jump on the project.

This fender is to see what problems I'm going to encounter before chopping up 2 brand new fenders. Once I get the 2 new fenders chopped and cleaned up. Then a mould will be made from them to make either fiberglass or carbon copies of them.



The cut off portion of the fender will go straight down, then curve 90 deg back to the factory mounting position under the car. That progress will be made this weekend for sure.
Attached Thumbnails Aerodynamic Discussion Thread-20130328_110138_zpsfb87127e.jpg   Aerodynamic Discussion Thread-20130328_110153_zps7e16115f.jpg  
Old Mar 28, 2013 | 03:08 PM
  #137  
ThePass's Avatar
Supporting Vendor
iTrader: (3)
 
Joined: Jul 2006
Posts: 3,310
Total Cats: 1,236
From: San Diego
Default

Originally Posted by mx5autoxer
Ah good. I was hoping you'd reply, Pass. Is there any situation where it would be negative? For instance is it better for a track with a lot of high speed corners or a track with long straights?
I would think it probably creates a little more drag than an oem fender, but it should reduce lift. Take that info for what it's worth, which is $0.00 I am just a self-educated hobbyist applying what is generally known to work without the ability/budget to do any sort of worthwhile testing on the little bits like this to tweak them, so they may not be optimal.

-Ryan
__________________
Ryan Passey
Old May 19, 2013 | 03:23 PM
  #138  
1993ka24det's Avatar
Thread Starter
Senior Member
 
Joined: Oct 2011
Posts: 646
Total Cats: 62
From: The Race Track & St Pete FL
Default

This is something I seen on the Mclaren GT3, a multi element dive plane. I'm guessing more efficiency with the steeper angle.

Attached Thumbnails Aerodynamic Discussion Thread-mclaren-gt3-front-hd-wallpaper_zpsa5c24977.jpg  
Old May 20, 2013 | 12:38 AM
  #139  
cordycord's Avatar
Elite Member
iTrader: (2)
 
Joined: Dec 2011
Posts: 3,398
Total Cats: 560
From: SoCal
Default

Originally Posted by 1993ka24det
This is something I seen on the Mclaren GT3, a multi element dive plane. I'm guessing more efficiency with the steeper angle.

Same concept as a multi-element rear wing, i'd imagine.
Old May 20, 2013 | 01:09 AM
  #140  
mx5-kiwi's Avatar
Senior Member
 
Joined: Dec 2010
Posts: 993
Total Cats: 57
From: Auckland, NZ
Default

I thought canards are to disrupt airflow down the side of the car (by reducing airflow entering underneath from the side) that being the case maybe the small gaps help create more/multiple disruptive vortice's than just the single trailing edge of a one piece?

Multi plane wing is for aerodynamic efficiency I wouldn't have thought an efficient down force generator there is the idea...unless it / canards do both?



One other key point, my car has a front air dam that is angled up for kerbs/clearance etc. Somewhere (this thread?) I asked if you could run a splitter even if the angle was not flat....it would appear Mclaren think you can....



All times are GMT -4. The time now is 09:06 PM.