So, just How many Dimples are there on a Golf Ball?
Well, the number of dimples on a typical golf ball is generally 336 but, the number of dimples on a golf ball can range anywhere from 300 to 500 depending upon the golf ball, manufacturer and dimple design.
Golf Ball Dimple Shape, Alignment and the Dimple Effect
Though the swing of the golf club provides the impact, it's the design and construction of the golf ball that makes it go. Golf balls with a harder core (high compression ratio) travel further because they deform less upon impact and produce a greater transfer of energy, and then there are the dimples.
The dimples on a golf ball may vary in size, shape, depth and configuration, they all share a common purpose to provide longer and higher flight to the ball. A dimpled golf ball can travel two to three times as far as the same ball with no dimples. The dimples allow air to flow over the golf ball, providing less drag. Also, hitting a golf ball results in a rapid backspin, this forces airflow downward and creates an opposite upward force that provides lift.
Why do Golf Balls have Dimples?
Golf ball dimples refer to the depressions on the surface of the golf ball, which have a significant effect on golf ball lift and how far a golf ball travels. This fact has prompted a great deal of research on golf ball dimple shape and alignment. In recent years, golf ball manufacturers have even introduced “dimple plus” alignments, in which seam lines have been eliminated. Dimples on a regulation golf ball differ greatly from one golf ball manufacturer to another, as well as the impact they have, depending on dimple alignment and the depth of the dimple depressions.
Dimple Configuration shown to the left, is an Octahedral 392 dimple configuration and an Icosahedral 432 dimple configuration respectively.
Golf Ball Dimples Increase Lift and Reduce Air Resistance
Dimples marked onto the surface of a golf ball are not simply for decorative purposes. Golf ball dimples play a major role in determining the distance traveled by the golf ball. Two of the principal effects of golf ball dimples are to increase lift and reduce air resistance, which results in longer distances traveled and greater stability in shot trajectory. Although golf ball dimples appear to be all alike to the untrained eye, they do in fact come in a variety of dimple patterns.
Their impacts differ depending on dimple alignment and the depth of depressions. The number of dimples on a ball is also a consequence of alignment and depth. The number of dimples generally range between 350 and 500 dimples per golf ball, their numbers do not significantly affect distance.
Ideally, dimples should be spread evenly across the surface of the ball in recurring combinations of one shallow and one deep dimple. If this cannot be done with precision, golfers will lose distance on their shots, or find them veering to the left or right -- even on shots where the ball has been hit squarely on center.
Effect of Dimples on Golf Ball Distance and Trajectory
The discovery of the effect of dimples on golf ball distance and trajectory was almost by accident back in the mid 1800's. It was discovered that golf balls with improperly smoothed surfaces often flew straighter and further than their smooth counterpart. Thus the "Hand Hammered Gutta- Ball" was formed. These golf balls were hammered by hand with a consistent pattern using a sharp edged hammer.
Dimples and the Boundary Layer
We have known since the mid 1800's that dimpled golf balls fly much further than smooth golf balls. The boundary layer is the thin layer of air surrounding a golf ball as it flies through the air. In the boundary layer, the speed of the air varies from where it contacts the air on the surface of the ball (which is not moving relative to the ball), to where it contacts the mainstream airflow, at the outer edge of the boundary layer.
So, just why do dimpled golf balls fly further?
Dimpled golf balls travel further than smooth golf balls is because the dimples on a golf ball create turbulence in the boundary layer. This actually helps reduce drag and increase lift. The dimples actually scoop up air and move it back towards the rear of the ball as the ball spins. By moving more air to the rear, you can -- in effect keep the air pressure behind the ball from dropping. By doing this, the amount of air pressure pulling backwards on the ball is decreased creating less drag.
Dimple Effect on Golf Ball Trajectory...
Golf Ball Dimples Increases Lift
On a golf ball hit with back spin, dimples will cause currents of air moving above the ball to move faster, thus lowering air pressure and promoting lift.
Golf Ball Dimples Reduce Air Pressure
Dimples facilitate the movement of air to the back of the ball, preventing the reduction of air pressure behind the ball. This lessens the amount of air pressure pulling toward the rear of the golf ball.
Golf balls without dimples produce no lift, and fail to travel for any significant distance because they are unable to rise to any significant height in their shot trajectories. As dimples are made shallower, trajectories tend to rise, while the deeper the dimple the less the trajectory.
In order to make a typical golf ball travel up to three times the distance with dimples than without, there is an ideally appropriate dimple depth that must be provided.