Aerodynamics of Golf Balls :: physics sport sports golf

Introduction to Aerodynamics Aerodynamics is the study of the motion of fluids in the gas state and bodies in motion relative to the fluid/air. In other words the study of aerodynamics is the study of fluid dynamics specifically relating to air or the gas state of matter. When an object travels through fluid/air there are two types of flow characteristics that happen, laminar and turbulent. Laminar flow is a smooth steady flow over a smooth surface and it has little disturbance. Intuition would lead to the belief that this type of air flow would be desirable. It would make sense to assume that this smooth undisturbed air would create the least amount of resistive force due to friction. The golf ball seemingly defies this theory by traveling farther with its disruptive surface texture that creates the second flow characteristic, turbulent flow. Turbulent flow is flow that is disturbed and creates whirlpool like features. The turbulent air actually lessens the difference in velocity of the air layer that is extremely close to the ball compared to the rest of the air and so lessens the friction acting on the ball. Drag is a major contributor to how an object travels through fluid/air. Drag is caused by the disrupted air immediately behind an object moving through fluid/air. It acts perpendicular to and in the opposite direction of travel of the object and impedes the motion of the object. It would make sense that if the drag is minimized the object will travel farther. Lift or curve in the motion of an object through air is a phenomena that is noticeable in a ball traveling through fluid/air. This change in direction is due to the effect that spin has on the object in motion. This can be explained by Bernoulli's Principle. Bernoulli, a 1700's physicist and mathematician, showed that the speed of an object through liquid/air changes the pressure of the air. The velocity of a spinning ball relative to the air is different from one side to the other creating a low pressure on one side and a high pressure on the other. This causes the ball to move in the direction of the lower pressure. The golf ball is typically hit with an undercut causing a reverse rotation and therefore a lifting action on the ball. The History of Golf Balls The golf ball has changed dramatically through the years. Smooth hardwood balls were used between the 1400 and 1700's.