Golf Balls

[JackD]

so thats why Dolan showed up at the NW Reunion sans tux and shoes..............

I made more money with no shoes, the halter top, and the tats.

OBTW: There is hope for Kent and I have decided to let him live. 

[oz]

excellent now thats funny orange balls it is best set up at the bend in the road we dont want to damage the course.   

[Seldom Seen Slim]

Yeah, Corbin.  That's what I meant.  Who got into the post and switched what I said from Corbin to Vetter?  Damn vandals are at it again.

Thanks, Kent.

[edweldon]

Can't resist throwing in my 2 cents on this one.  Creative; maybe whacky; don't really expect anyone to do this; but..............
Make a steel roller for your wheeling machine with dimples.  After you machine and heat treat it carefully layout and mark the pattern of dimples on the roller surface and mark them with dots of resist paint. Then acid etch the steel away to a depth of 20-30 thou.  Build a bottom roller of steel with a thin hard rubber tread.  Prototype dies to test the process can be just made of flat steel and tested in your hydraulic press that you put a pressure gauge on. Figure out the best diameter depth and spacing of the dimples, how to etch them and what thickness, durometer and adhesive to use for the lower roller. That way you won't go broke buying tool steel for the rollers to experiment with.
Now you can roll your pattern into the aluminum sheets for the top, side and belly pan panels.  Then when you're all done and decide whether or not it makes the car go faster just think ------- what a neat way to make non skid panels for your flooring (another useless idea)
Ed Weldon
Los Gatos (on the far side of the mountain), CA

[willieworld]

hey ed   willie here  wernt you the inventer of the solor powered flashlight   opps here come the forum cops   willie buchta

[Dynoroom]

gee...... I thought the dimples in a golf ball were there to help keep it aloft............ so it could fly farther.......... hmmm 

[maguromic]

Dimples have been in practice on golf balls since the 1930’s when research showed that they will help increase lift and reduce drag, but have yet to transfer to the racing world.  Ferrari F1 tested dimples in a wind tunnel but didn’t go beyond that.  Most likely the rules guys stopped it.

There has been some research in the Texas A&M low speed wind tunnel on wheel disks with dimples, which showed very good Reynolds numbers compared to non-dimpled wheel disks. They concluded any where from hexagons to icosahedral (20 sided) shapes worked well as the corners that trip the airflow to create the effect. The drag reduction and wake reduction was considerable also.  But the practical side, it is very expensive and difficult to make multi sided dimples.

There is a Lexis that comes with dimples on the floor to reduce noise.  Is this reducing noise by reducing drag? Is this why the intake ports in a head are a little rough vs very smooth?  There is a pretty good article in Race Car Engineering Oct. 2006 on this subject.

Just food for thought and something to consider.

[rustyT]

Guys and Gals.
I have tested the theory of dimples many times,when panels or other parts that I build havent fit,I have put many "ballpien dimples" and thrown them,doesnt seem to fly any further than peices without dimples. Didnt know I was doing R&D until just now.
                                         Phil.

[interested bystander]

Not important to the topic probably, but my dad had Goff balls that had little SQUARES all over them (from the late '30s/early '40s).

Remember the flight of the golf ball - it tumbles over and over and over- might not be too desireable with yer racer!

[Milwaukee Midget]

I seem to remember Richard Petty running a dimpled vinyl top on his '68 Plymouth.  Didn't seem to help him much, other than to psych out the other drivers.

[Rex Schimmer]

The old saying down south about Richard Petty was, "If Richard won a race dragging a dead cow behind his car there wouldn't a cow in the county come the next race!".

He did a lot of head work on his competitors.

Rex

[Darcane]

Look at this stuff, somewhat the same principal and no you down want dimples on the front.........

Wings and Wheels ...............

http://www.wingsandwheels.com/page29.htm

.................... Sealing Tapes and Control Seals along with Zig-Zag Turbulator and Dimple Turbulator Tapes (also called trip tapes -- "they create a rough place for the laminar flow to "trip over" into minor turbulence before separation occurs due to body shape. This reduces drag because this turbulence keeps the flowing air closer to the body than if it wasn't there, therefore reducing profile drag.", the Rev. H+.

Also here................

http://purplesagetradingpost.com/sumner/bvillecar/bvillelinks.htm

.................I have a lot of aero links under "Aerodynamic Info and LSR Calculator/Spread Sheet Sites",

Sum

I think you've got the theory of why it works figured out.  It's the same reasoning behind the vortex generators that come stock on some Mitsubishi Lancers.  I'd guess dimpling could even be considered to be vortex generators (VGs).

Streamliner and lakester classes wouldn't benefit much if at all by them since they tend to be designed so that you don't get the flow separation where the VGs become helpful.  Where VGs would be most beneficial are on cars that are relatively stock bodied like /GC or /PRO.  But...  if I read the rule book right, vortex generators are prohibited in those two classes.

Mike

[maguromic]

Mike, the rulebook is pretty clear on what a vortex generator is  “ Sharp edged devises placed on the body for the proposes of creating flow vortices”.  I don’t think dimples would fall into this category from a definition standpoint.  You could create he same effect with a properly textured paint job.

Some of the NASCAR boys have figured this out and have gone with the full body wraps.  They use a product called Control Tec, by Scotch.  Cant remember the thickness of the product but it has an interlocking pattern to it.  The company response is that it helps with applying the material on to the car, but a definite plus is the textured feel.

It is next to impossible trying to write a rule for this.  Its like policing traction control.

[edweldon]

Posted by -- maguromic, Location: Palo Alto, CA  Re: Golf Balls
« Reply #21 on: March 20, 2008, 11:12:47 PM
There has been some research in the Texas A&M low speed wind tunnel on wheel disks with dimples, which showed very good Reynolds numbers compared to non-dimpled wheel disks. They concluded any where from hexagons to icosahedral (20 sided) shapes worked well as the corners that trip the airflow to create the effect. The drag reduction and wake reduction was considerable also.  But the practical side, it is very expensive and difficult to make multi sided dimples.
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HA!!.  So it's in the public domain.  No point in rushing to the patent office.  Who wants to be a millionaire?  Here's the DNA for the business plan...............Next automotive aftermarket equipment craze.  Out with silly "Tonka" wheels.  In with wheel discs that not only evoke the bleeding edge of high speed Bonneville technology for increasing mileage through streamlining; BUT ALSO allow ventilation for everyday cooling of disc brakes.
Aluminum wheel discs Bonneville style spun from .060 dia perforated aluminum aluminum sheet and use OEM style wheel disc attaching hardware. 
"Your cake and eat it too" for only $400 a set of 4.  Or if you insist on a pretty pattern for the holes do them with a CNC turret punch before you spin them.  Maybe even do custom patterns for 3x the regular price.
C'mon ------ One of you young Southland tigers with some fab shop contacts and enough whits to promote it right go make enough bucks off of this to fund a serious streamliner project!!  Who's gonna do it??
Ed Weldon (this old man needs absolutely no piece of the action -- it's a freebie!)

[Darcane]

Mike, the rulebook is pretty clear on what a vortex generator is  “ Sharp edged devises placed on the body for the proposes of creating flow vortices”.  I don’t think dimples would fall into this category from a definition standpoint.  You could create he same effect with a properly textured paint job.

I have a 2006 copy of the SCTA rulebook which may be a little outdated.  Section 4.CC.8 simply reads "Vortex Generators: Aerodynamic devices mounted on the body for the purpose of creating flow vortices".  That seemed generic enough to me to cover a wide range of aerodynamic trickery.

Mike