Aerodynamics is the science that studies objects moving through fluids, whether air or liquids. Nowadays, aerodynamics is one of the most important factors in improving a Formula One car's performance: maximum downforce and dynamic stability with minimum drag. It is one of the few elements of development that can deliver performance gains race on race.
Driver clubheads have dramatically increased in size since the 1990's to the actual maximum permitted size of 460cc. As a result, the wind resistance and drag of the heads has also increased substantially, creating a heightened importance for applying proper aerodynamic engineering to their design.
All golf drivers generate a lot of diversion of airflow around the clubhead with pressure differences between the crown, sides, and sole. Because of the larger profile and no aerodynamic management, a 460cc driver has increased pressure drag and airflow instability compared to a smaller clubhead. This results in greater difficulty in consistently square the face at impact.
The first goal in golf aerodynamics is to achieve a minimal drag for the target swing speed of 90mph ± 25mph. Drag can be reduced by introducing aerodynamic elements around the club such as the Trip, Winglets, and Diffuser, as well as through surface treatments. Located on the front leading edge of the crown, the MR Driver features a Trip, which helps transition laminar airflow into turbulent airflow over the clubhead, in turn reducing the pressure wake created by the clubhead and less drag in the boundary layer. Without the Trip, the airflow would not transition into turbulent flow until towards the rear section of the crown, creating increased drag. The combination of the Diffuser on the skirt and Winglets on the toe and heel of the clubhead aids in pressure recovering resulting in lower wake, thus lower drag. To increase velocity of the airflow moving through the sole of the clubhead, a Venturi channel with a "shark-skin" Riblet pattern is integrated. As airflow is stagnant (more drag) where it meets a smooth surface, this Riblet pattern creates a rough surface in which it decreases drag by creating more turbulent air near the surface. This reduction in drag leads increased airflow to the Venturi channel, which further accelerates airflow to the Diffuser. This low pressure on the underside of the clubhead, along with the directional diffuser, helps the clubface to consistently square on impact while delivering a penetrating trajectory.
A golf swing is a very complex movement and no swing is alike; some players need a head that toes in as they struggle to close the club at impact whereas others, usually stronger golfers, fear hooks so need heads that tend to stay open. This is the second goal achieved through aerodynamics. With access to more than 200 leading Formula One aerodynamicists and materials scientists, two wind tunnels and Williams' state of the art CFD design capabilities, Williams Racing Golf has developed unique aero structures to help both kinds of players.
Our aerodynamics work in golf has also helped to improve energy transfer at impact. Larger club heads have the inherent problem of less stability and aero vibration; manufacturers have sought to address this problem by placing moveable weights and adjustable hosels.
Unfortunately these solutions actually result in two big losses of energy transfer: one produced by the displacement of the centre of gravity from strictly behind the ball and the second caused by the undesirable flexing of movable parts (screw) within the adjustable hosel. This typically reduces a golfers' club energy at impact by over 13%. (At 90mph, 20° displacement of centre of gravity equals 6% loss of impact energy while a metric 5 screw fixing a hosel produces an energy transfer loss of 7% in the World's strongest alloy).
Furthermore, the improvement of impact energy transfer together with the reduced drag improves the feel of the MR Driver helping to reduce muscle memory fatigue that comes from hitting several drivers consecutively. This allows players to better understand their swing patterns and reduce the amount of strength needed to swing the driver without compromising speed or distance.
Consequently Williams Racing Golf has established principles to never compromise our drivers' performance: the centre of gravity is kept strictly behind the ball and our hosels are cleverly designed to permit maximum transfer of energy at impact.