- Jun 8, 2016
- 16,118
- 113
Lol..I am off the clock. Maybe later..pattar, how about some knuckleball science?
Lol..I am off the clock. Maybe later..pattar, how about some knuckleball science?
This is just a guess...pattar, how about some knuckleball science?
This is just a guess...
First thing to note is that balls without seams knuckle, for example soccer balls so one can assume that it isn't (predominantly) a seam effect. So with that assumption, the fluid dynamics of non-rotating smooth spheres is pretty well known. For a certain range of Reynolds numbers (a non-dimensional number which combines velocity, diameter and air viscosity) unsteady vortex shedding occurs. Here is simulation of that effect over a cylinder (same idea):
This causes unsteady (e.g. time-dependent) forces to be generated on the ball which is why you see the ball dart in different directions..the force is not constant and is changing in time.
This same physics actually caused this:
This is just a guess...
First thing to note is that balls without seams knuckle, for example soccer balls so one can assume that it isn't (predominantly) a seam effect. So with that assumption, the fluid dynamics of non-rotating smooth spheres is pretty well known. For a certain range of Reynolds numbers (a non-dimensional number which combines velocity, diameter and air viscosity) unsteady vortex shedding occurs. Here is simulation of that effect over a cylinder (same idea):
This causes unsteady (e.g. time-dependent) forces to be generated on the ball which is why you see the ball dart in different directions..the force is not constant and is changing in time.
This same physics actually caused this:
Edit: Whether that phenomena caused that is still up in the air actually..some other physicists give a valid explanation why it wouldn't be the cause..in any case luckily they know not to design bridges like that anymore