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Laminar Express

pattar

Clueless..
Jun 8, 2016
3,995
113
There is still a lot of conjecture about the exact cause of the force that makes the ball break. There are more posts in the thread that I linked to that update the author's thinking. Turbulent air moves faster laminar flow air so is it Magnus Effect? The author thinks it is due to the differences in the wake on each side of ball that. The wake is affected by the seams.
The asymmetric wake is a byproduct of the location of the separation points on the third and 1st base sides and not the direct cause of the force. The force on the ball is due to the pressure distribution on the ball. Also turbulent flow is indeed faster than the laminar flow (when all other parameters are the same) but you are getting cause and effect wrong..it isn't faster because it is turbulent but turbulent because it is faster...
 
Nov 8, 2018
445
43
Bottom line for me.
Where do the stitches need to be and how do they need to rotate to get the ball to turn into a righty batter. ? Other than completely opposite a palm up curve ball.
As my dd pc I would love to get her to throw a screw
Ball without all the crazy techniques out there. She is ir and a screw ball spin isn’t going to happen. But with this theory we may be able to use it to MAKE the ball move that way.

Anyone ?


Sent from my iPhone using Tapatalk
 
May 15, 2008
589
28
Cape Cod Mass.
The asymmetric wake is a byproduct of the location of the separation points on the third and 1st base sides and not the direct cause of the force. The force on the ball is due to the pressure distribution on the ball. Also turbulent flow is indeed faster than the laminar flow (when all other parameters are the same) but you are getting cause and effect wrong..it isn't faster because it is turbulent but turbulent because it is faster...
So when the air hits the seam it speeds up and the increase in velocity causes the turbulence?
 
May 15, 2008
589
28
Cape Cod Mass.
Bottom line for me.
Where do the stitches need to be and how do they need to rotate to get the ball to turn into a righty batter. ? Other than completely opposite a palm up curve ball.
As my dd pc I would love to get her to throw a screw
Ball without all the crazy techniques out there. She is ir and a screw ball spin isn’t going to happen. But with this theory we may be able to use it to MAKE the ball move that way.

Anyone ?


Sent from my iPhone using Tapatalk
This is the tough part, trying to get something practical from all the theory. First we have to assume that it makes no difference whether the ball has backspin or topspin. If that is true then after looking at the baseball videos of pitches breaking in to the RH hitter I would guess that the axis of spin should be roughly aligned with the first baseline, and the direction of the spin would therefore line up the third baseline. I'm guessing that this would mean throwing a drop with the spin being tipped in the manner described. Also keep in mind that the centers of the "horseshoes" on opposites sides of that ball cannot both be on the center axis of spin. The rear seams are more important. I would take a ball and put a quarter size black spot in the center of one 'horseshoe". Then find the spot on the center axis on the other side of the ball and put a dime size spot there. Have your daughter take a two seam grip with the larger spot on the inside of her hand. When she delivers the drop if the axis is tipped and the rotation is true she should see the large spot on the left back side of the ball and you should see the small spot to your left front side of the ball. To make it work the rotation (spin axis) needs to be properly aligned and the seams have to be located in the right spot.

I have been experimenting with just a two seam fastball and sometimes there is some break but it's tough getting everything working at once.
 

pattar

Clueless..
Jun 8, 2016
3,995
113
So when the air hits the seam it speeds up and the increase in velocity causes the turbulence?
The author is claiming that they have found that the flow is already turbulent before it encounters any seams or any roughness on the ball hence his statement at the end about scuffing the ball. His theory is that the flow separation due to the seams is causing the movement and not transition to turbulence.

With respect to your general question regarding turbulence, it is a phenomena whereby once you increase the velocity beyond a certain point, for a given surface (and keeping every other flow parameter the same), the flow will become turbulent.

https://en.wikipedia.org/wiki/Turbulence
 
Last edited:
Mar 20, 2015
117
18
Also keep in mind that the centers of the "horseshoes" on opposites sides of that ball cannot both be on the center axis of spin. The rear seams are more important.
Good point. If the theory in this article is correct then then yes the grip would need to be adjusted so that its not a pure 2 seam pitch to keep the rear seam aligned in one spot and not moving around as the ball spins. Going to try this with DD to see if there is any effect.
 
May 15, 2008
589
28
Cape Cod Mass.
The author is claiming that they have found that the flow is already turbulent before it encounters any seams or any roughness on the ball hence his statement at the end about scuffing the ball. His theory is that the flow separation due to the seams is causing the movement and not transition to turbulence.

My confusion about this is due to my reading all of the Dr Smith's posts, this is from a later one:

"I have said in the past (based on rough, high-seam balls) that the boundary layer of a baseball at 90 mph is always turbulent, but I may have to walk that back. "

He does say a new ball with smooth leather has laminar flow on the forward hemisphere.
 
May 15, 2008
589
28
Cape Cod Mass.
Good point. If the theory in this article is correct then then yes the grip would need to be adjusted so that its not a pure 2 seam pitch to keep the rear seam aligned in one spot and not moving around as the ball spins. Going to try this with DD to see if there is any effect.
The difficulty with trying to reproduce the MLB effect with a ball that breaks in to a RH hitter is that it requires topspin with a slight twist of counter clockwise bulletspin, not easy to do. You might also be able to do it with a 'risecurve' and the proper two seam orientation.
 

pattar

Clueless..
Jun 8, 2016
3,995
113
My confusion about this is due to my reading all of the Dr Smith's posts, this is from a later one:

"I have said in the past (based on rough, high-seam balls) that the boundary layer of a baseball at 90 mph is always turbulent, but I may have to walk that back. "

He does say a new ball with smooth leather has laminar flow on the forward hemisphere.
Yeah.. I don't the know the answer to whether the boundary is turbulent or not. The theory he gives in that post is based upon the assumption that it is. If it isn't then the effect would be a combination of turbulence and flow separation I guess.
 
Mar 20, 2015
117
18
The difficulty with trying to reproduce the MLB effect with a ball that breaks in to a RH hitter is that it requires topspin with a slight twist of counter clockwise bulletspin, not easy to do. You might also be able to do it with a 'risecurve' and the proper two seam orientation.
Wish we could get it to break in but just going with the regular IR fastball spin and having it break out. Unlike a baseball 2 seam fastball it is spinning clockwise towards the RH batter with yawed overspin.
 
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