Double Diffuser

A double diffuser is an aerodynamic device used on Formula 1 cars that features two levels of airflow channels at the rear of the car to create extra downforce and improve grip on the track.

To understand how a double diffuser works, think of it like a vacuum cleaner in reverse. Regular diffusers speed up air flowing under the car, which creates lower pressure underneath and literally sucks the car down to the track. This downward force, called downforce, helps the tires grip better during high-speed cornering.

The double diffuser takes this concept further by adding a second layer or "deck" above the main diffuser. This upper section processes additional airflow through carefully designed openings in the car's floor. By handling more air through two channels instead of one, the double diffuser generates significantly more downforce than a standard single-level design.

This technology became famous during the 2009 Formula 1 season when three teams - Brawn GP, Toyota, and Williams - introduced double diffusers on their cars. The other teams initially complained that these designs were illegal, but racing officials ruled them legal because they cleverly exploited gaps in the technical regulations.

The Brawn GP team's double diffuser was particularly successful, helping driver Jenson Button win the World Championship that year. The extra downforce allowed their car to corner faster and put less stress on the tires during races.

Once the design was confirmed legal, nearly every team rushed to develop their own double diffuser systems. This created an expensive development battle as teams tried to maximize the aerodynamic advantages.

However, the double diffuser era was short-lived. Racing officials changed the rules after the 2010 season to specifically ban these devices, believing they gave some teams an unfair advantage and made the sport too expensive for smaller teams to compete effectively.