What is Digg?104 Comments
- Tichondrius74, on 12/10/2008, -1/+42That was very soothing video.
- darkcrystal, on 12/10/2008, -0/+30Sounds like the voice was made by the supercomputer...
- Dujenwook, on 12/10/2008, -0/+25Seems like a brilliant use of supercomputer time to me.
- Megadeth222, on 12/10/2008, -2/+25They should make airplanes dimply too
- kirb59y, on 12/10/2008, -0/+15Epic Narration
- inactive, on 12/10/2008, -0/+14The dimples trip the boundary layer into becoming turbulent, reducing separation drag greatly while increasing friction drag slightly. A net drag reduction results.
Back to studying for my viscous flow final... - inactive, on 12/10/2008, -1/+12Dude, LiveScience.com, not cool. Golf balls trusted you with their secret, and you went and outed them? You guys are *****.
- gwellington, on 12/10/2008, -0/+10Because an airplane wing isn't a sphere. And they have tried it.
- zzzpoohzzz, on 12/10/2008, -0/+10too bad my golf game isnt very soothing.... it makes me swear as much as mario kart
- inactive, on 12/10/2008, -1/+10Because a dimpled airplane would fly so fast the high G force would stretch your face into the seat.
- ophello, on 12/10/2008, -1/+7I learned nothing new, but I somehow feel smarter.
Quite interesting. - Ghengis, on 12/10/2008, -0/+6It's somewhat of a waste if they don't ad the ball's spin to the simulation. This spin directs the vacuum which trails the ball to not be directly behind the ball, adding lift and curve to the ball's flight, which also contribute to it's ability to fly farther. Maybe they need the new i7s from Intel to add that variable ;)
- BrutusOSU45, on 12/10/2008, -0/+6Because the dimples create turbulence. There is already turbulent flow around the wing of an aircraft because of the high Reynolds number so to add dimples to it would be a waste of time. Also because it would look really fugly.
- OneLess, on 12/10/2008, -0/+5Too much turbulent flow over a wing causes boundary layer separation:
http://www.youtube.com/watch?v=J-xxCkebdZs
Which leads to this:
http://www.youtube.com/watch?v=J9tn2pogL6A - Rbstr, on 12/10/2008, -0/+5It has to do with when the fluid around an object becomes turbulent (and a thing called the reynolds number)
Dimples don't work on a plane because the air around the plane is already turbulent do to the plane's high velocity.
Golf balls would not cause the turbulent flow if they were smooth because they have a small radius and velocity.
Adding the roughness allows the golfball to transition into turbulence at it's surface.
It's simply luck that air and golf balls have the right properties to show this phenomenon.
Baseballs and their laces are also impacted by the same thing! - Johnnyhorse, on 12/10/2008, -0/+5Well. It was a nice graphic anyways.
It would have been nice if they actually compared it to something. - OutpostNetwork, on 12/10/2008, -0/+5The ball doesn't go through the air that way. The ball is spinning backwards as it is hit off the club face. The dimples are there for lift. This video doesn't really prove anything that isn't already known.
Also to say that there are no rules or regulations against the number of dimples, how deep they are etc. is irresponsible reporting. All facets of the golf ball are governed by the USGA and R & A. - inactive, on 12/10/2008, -0/+4Actually, when you get into fluid dynamics it gets very complicated.
- mecharabbit, on 12/10/2008, -1/+5My thought exactly. Please tell us, aerodynamics experts, why aren't our airplanes dimply?
- cknyan, on 12/10/2008, -0/+4Wish 20% of the shows on Discovery Channel used a similar presentation style. Instead of dumbing it down for the A.D.D. crowd they give the facts and leave the the view in awe.
- ophello, on 12/10/2008, -0/+4Mostly, when golf balls used to be smooth and made of wood, golfers found that the well-worn and abused balls traveled farther. Hence, the preference for dimples was born.
- zenerdiode, on 12/10/2008, -0/+4They have an equivalent: Vortex Generators. They perform the same function yet do not have as much friction drag problems of dimples. The generate vortices which disrupts the laminar boundary layer and pushes it in into the turbulent range. Generally, only smaller, slower planes use em since as you get to the transonic and supersonic range, most of your flow is going to be turbulent anyways. Obviously, you can see why vortex generators don't work so well on golfballs.
http://en.wikipedia.org/wiki/Vortex_generator - sathias, on 12/10/2008, -1/+5From the link
"Sporting goods companies have been relying upon trial and error to create effective dimple patterns. Now they may have a much better tool." - pbcar, on 12/10/2008, -1/+4 Yes, if you want them to fall out of the sky.
- CalcProgrammer1, on 12/10/2008, -0/+3I know, who on earth would consider gold (an expensive yellowish metal) a sport? Really, tell us something worth telling next time.
- doublefelix, on 12/10/2008, -1/+4This was also revealed to be Kirk Douglas' secret.
- ripple123, on 12/10/2008, -0/+3captains log... stardate 4931... i am... so very.... very.... high....
- sockpuppets, on 12/10/2008, -1/+4That's what she said.
- Chris_F, on 12/10/2008, -0/+3So when my girlfriend took a bat to the hood of my car, it was to make it faster?
- WeaponAlpha, on 12/10/2008, -0/+3You are obviously not a mechanical engineer.
- Lord_oftheTrons, on 12/10/2008, -1/+4Did you WTFV?
- TrevorPace, on 12/10/2008, -0/+2Airplanes don't tumble through the air. At least not usually.
- inactive, on 12/10/2008, -0/+2So does this mean fat chicks with cottage cheese legs get better gas mileage on motorcycles?
- Brookese, on 12/10/2008, -0/+2So why aren't the hoods and roofs of racecars dimpled?
- yourbrokenoven, on 12/10/2008, -0/+2old old old old news. no digg.
- scoottie, on 12/10/2008, -1/+3its not really a secret
- BoneheadFarker, on 12/10/2008, -1/+3If dimples on a golf ball helps air flow over the surface, then why has no one attempted this on the topside of a plane wing?
- u8myfoood, on 12/10/2008, -1/+3http://www.youtube.com/watch?v=jPVJXUrg6oM
Explanation by Bill Nye and Samuel L. (Mother *****) Jackson - ophello, on 12/10/2008, -0/+2airplanes are not traveling at low velocity. at 600mph, dimples would tear off the aluminum siding. At high velocity, the rules change.
- OneLess, on 12/10/2008, -0/+2Boundary layer separation on a wing is called a stall.
- ClevelandBrown, on 12/10/2008, -0/+2yeah, good for you/your pop.
- Denominator88, on 12/10/2008, -0/+2Surprised no one mentioned Bernoulli's Principle.
- Diggsterrr, on 12/10/2008, -1/+3All I know is, Pro-V1's FTW!
- tpfaff, on 12/10/2008, -0/+2too hard, i like a softer ball (no *****)
- KidTechno, on 12/10/2008, -0/+1hexagons > circles. its all about surface area.
http://www.callawaygolf.com/Global/en-US/Innovatio ... - bullsfan03, on 12/10/2008, -0/+1Dugg for pie.
- Contrapulator, on 12/10/2008, -0/+1Flat and smooth isn't the greatest in aerodynamics. This reminds me of the recent discovery that the tubercules (bumps) on whale fins increase lift efficiency and stall resistance. http://dsc.discovery.com/news/2008/07/11/wind-turb ...
- djjester, on 12/10/2008, -0/+1This dimpling was also intentionally done on canon balls for ages.
- CaviMike, on 12/10/2008, -0/+1Exactly. I would have at least liked to see it against a smooth golf ball.
- CaviMike, on 12/10/2008, -1/+2Why do science commentators have to sound so cheesy? Do they all think that Captain Kirk was really a pimp?
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