Aerodynamically, bargeboards act primarily as
flow conditioners, smoothing and redirecting the turbulent or "dirty" air in the wake of the front wing, the front suspension links, and the rotating front wheels. Part of their function is to direct the turbulent wakes of the front wing and spinning front wheels away from downstream aerodynamic surfaces. In this capacity, they separate different components of this mixture of flows, and direct them either outside and around the sidepods, or direct flow towards the radiator inlets. As such, the configuration of bargeboards can have significance with respect to cooling. They also help direct flow behind the front wheels, reducing the wake drag created by the wheel profile.
Vortex generators Another important function of bargeboards is to act as
vortex generators, redirecting and energizing airflow. The upper, downward sloping edge can shed a large vortex downstream around the sidepods, where it can interact favorably with flip-ups, or aid in sealing the low pressure underbody flow from the ambient stream. The bottom edge of the bargeboard can also shed vortices that energize the airflow to the underbody, which can help delay flow separation and allow the use of more aggressive diffuser profiles. In recent years, these two edges have acquired relatively large serrations or protruding tabs to enhance this aspect of their performance. == Turning vanes ==