Polishing Intakes

[LightningGSX]

I was reading a thread from some time ago about polishing intakes and a few people said because golf balls have dimples and shark skin is rough, air flows better over rough surfaces.Since I didn't see anybody disagree with them I had to post this.That statement is not even close to being true and I hope nobody believes this.This is FACT not OPINION.

 

[Defiant]

Do a search for "laminar flow" and "boundary layer" and get back to us.

 

[91TalonTSiCT]

golfballs have dimples so you hit the ball "square", like balls at a batting cage and shark skin is smooth going from head to tail and rough from tail to head. idiots.

 

[LightningGSX]

Originally posted by Defiant
Do a search for "laminar flow" and "boundary layer" and get back to us.

I know of both "laminar flow" and "boundary layer",are you disagreeing with me?

 

[91TalonTSiCT]

no not at all. just about the golf ball and the shark skin thing that the person first posted.

 

[LightningGSX]

Oh yeah, golf balls have dimples to reduce pressure drag(low pressure behind the ball).I'm not saying your wrong about the square thing,but how would that work?

 

[91TalonTSiCT]

when a ball makes contact. its for the contact as well as the flight. that is why batting cage balls have dimples too. you are also obviously correct about the pressure too. but i was pointing out that "bc golfballs have dimples and shark skin is rough" is very vague, and somewhat misleading

 

[LightningGSX]

In the thread I was reading a couple people were trying to make a case for non polished intakes.One person said golf balls have dimples, so air must flow better over rough surfaces(Not True).Then another person said it must be true because sharks have rough skin...And I still don't see what your talking about on the square thing.The only sense I make of it is,the dimples make flat surfaces on the ball(from edge to edge of the dimple).But it would be pretty unlikely hitting one of these "square".

 

[kpt4321]

Defiant, would you like to explain this further?

""Use the Search" is not an acceptable response by itself.
Link to the answer and explain how the info can be found, or just move on and say nothing."

I agree with LightningGSX.

You will have the least aerodynamic resistance, with the maximum flow, with a smooth walled intake manifold (or ports).

On the other hand, the gains from polishing are minute, and not really worth the effort on a non-race car.


....Kyle T.

 

[91TalonTSiCT]

and kyle t has just summed it up!
after all the posts about porting and polishing people should know that they are both done for higher register RPM. where every little bit matters.

 

[Speede]

Originally posted by 91TalonTSiCT
golfballs have dimples so you hit the ball "square", like balls at a batting cage and shark skin is smooth going from head to tail and rough from tail to head. idiots.

not quite, they have dimples to create lift as they spin backwards -- this makes the ball slowly rise (when you hit it well, at least) until it slows down.

 

[Streetbeat]

did a search on askjeeves.com and came up with this off of www.thephysicsofgolfballs.homestead.com/dimples.html

"The dimples on a golf ball are extremely important to its flight. They make the ball travel farther and can also make the ball easier to control. The configuration of the dimples determines the ball's flight while the number of dimples is important to the distance the ball will travel.

A dimpled golf ball travels about four times farther than a golf ball without dimples. This is because of many forces that are present because of the dimples.The configuration of the dimples also plays a major part in the distance a golf ball travels. Deep, small dimples cause the ball to fly longer and lower. Large, shallow dimples give the ball great lift but the ball doesn't fly very far..Lift is the force that causes a golf ball to fly higher. A ball with a combination of both configuations has an equal amount of each.


Scientists who designed the dimpled golf ball thought that if some dimples helped the ball fly farther than one without them, than more dimples would make a ball fly even farther. They were wrong. Their tests showed that a ball with many tiny dimples flew just like a golf ball without dimples. It is now known that golf balls with 300 to 500 dimples fly the best. Regulation golfballs have 336 dimples on them."

 

[LightningGSX]

I doubt the dimples have anything to do with lift,to create lift the ball would have to have a non symetrical dimple pattern.Since the dimples are the same all around the ball,air moves the same speed on the top as it does on the bottom therefore no lift created.The major effect of the dimples is for velocity purposes only.In general they create surface friction which in turn gives the boundary layers of the flow separation more energy which lowers pressure drag(low pressure behind the ball).Not a complete explanation,but it should give a general idea.As far as intakes,in most apps the benefits are minimal but the benefits do exist.

 

[4g63swap]

just my opinion but your compairing apples and oranges. A golf ball like a shark is going through a medium (air/water), and intake lets the medium pass through it (air). Therefore you would want to create a path with the least amount of ressistance.........so in this case a polished intake would be benifical.
if that makes any sence

4g63swap

 

[LightningGSX]

I'm NOT comparing golf balls or sharks to intakes.Other people in other threads were and thats why I started this thread.Which you would know if you read the my original post.

 

[4g63swap]

sorry started to read then I got bord with the same stuff being said over and over so I just skip to the bottom.:laugh:

 

[LightningGSX]

The more I think about the "square" thing, it makes more sense to me.You would have some probability of hitting a flat spot on the ball.Making a better trajectory.

 

[jltcat]

you want a somewhat rough surface because it creates turbulance on the sidewalls so the air doesnt stick the the sides. It creates a "ball bearing surface" for the air to flow on. For exhaust you want smooth because it has soot mixed in with it.

 

[LightningGSX]

Originally posted by jltcat
you want a somewhat rough surface because it creates turbulance on the sidewalls so the air doesnt stick the the sides. It creates a "ball bearing surface" for the air to flow on. For exhaust you want smooth because it has soot mixed in with it.

Stick? is that a joke? The only place in the intake you want less then smooth is, anyplace fuel will be mixed with the air.Which is pretty much the intake ports in the head.Anywhere there is laminar flow ANY surface friction will add drag to the flow.Fuel on the other hand could puddle easier on smoother surfaces

 

[jltcat]

an example of what I mean. Take your hand and run it across a smooth surface. Then run it across a slightly rougher surface. Which slides easier?

 

[jltcat]

the difference between the flows wont really be noticable unless your looking for a difference of .01 in the quarter mile. The hp gain will be almost unmeasurable. unless you go to the severe edge of smoothness/roughness

 

[LightningGSX]

Thats pretty much what I said a few posts ago.

 

[jltcat]

when I said rough I didnt mean concrete block rough. Its going to be fairly smooth just not a mirror finish.

 

[LightningGSX]

And it is very measureable,has been measured,and is huge in some situations.I THINK like 10 to 15 HP in fairly modded engines

 

[91TalonTSiCT]

the hand across a flat surface isnt the same. your hand has tiny grooves in it called PRINTS. these grooves provide grip. Air does not behave in the same manner as a HAND over a flat surface. Air would like a path with least resistance. That is why airplanes and racecars have smooth surfaces and dont favor dirt because its not a ball bearing. thats a whole other issue in itself as well.