AERODYNAMICS
Golf Ball Aerodynamics
The interaction between the golf ball and the air is defined by the laws of aerodynamics. There are two primary aerodynamic forces: lift and drag.
Drag acts to slow down the golf ball. By reducing drag distances can be increased.
Lift is an upward force on the golf ball that needs to be optimised for maximum distance.
Dimples and Drag
Dimple patterns are designed to minimise drag, the force that opposes the golf ball’s motion.
Air that passes over a smooth golf ball remains laminar (smooth flow) and separates from the golf ball leaving a large wake behind the golf ball causing drag.
By adding dimples the air passing over the golf ball becomes turbulent (rough flow) and remains closer to the golf ball for longer, reducing the wake and thus reducing drag.
Dimples and Trajectory
Dimples can modify the way in which the golf ball travels through the air and in turn can affect how much lift is produced.
The total volume of all he dimples is the simplest factor dictating lift. The larger the total dimple volume, the lower the lift.
The physics of the lift (the Magnus Effect) are complicated. In simple terms, due to the backspin on a golf ball, the air travels faster across the top of the golf ball than it does across the bottom of the golf ball, leading to pressure differences and an upward force on the golf ball.
Designing Dimples
Like golf balls, dimple design has evolved over time. Manufacturers use cutting-edge technologies such as computational fluid dynamics to optimise the performance of dimple patterns.
Computer aided design (CAD) software is used to develop dimple design concepts.
Dimple designs are then tested using computational fluid dynamics (CFD) software and laboratory equipment to determine drag and lift properties.
Prototyping is used to complement the information obtained using computer analysis and achieve the best performing dimple patterns possible.