A Farewell to Vortex Generators in Formula One


2019 Front Wing Prototype on the 2018 Williams FW41.

Ian Wallace, Columnist

Lewis Hamilton has clinched the 2018 Formula One World Championship driver’s title, making the season—as well as the joy of watching the fastest Formula One cars in history—effectively over.  For 2019, an aerodynamic regulation change will render cars around a second and a half slower. A simplified front wing along with other minor changes along the sides of the car will mark the end of an era of vortex manipulation that began in the 1990’s, leaving teams with less options to manipulate the airflow around their cars, trading speed for easier overtakes.  The fastest sport on earth is about to get slower for an indefinite period of time.

The inwash and outwash vortices on the 2017 Mclaren MCL32

The primary purpose for vortex generators on a Formula One car is to protect the downforce-generating clean air from the dirty air caused by the exposed tires.  In the diagram to the right, the front wing generates two vortices, one called the outwash and the other called the inwash. The outwash vortices direct air around the aerodynamically inefficient tires, reducing their drag, while the inwash vortices prevent the disturbed wake from the tires from travelling to the rear wing.  With vortex-generating winglets on the front wing banned, the outwash effect will be blocked unless teams find a loophole in the regulations. The front wing endplates, which are part of the vortex generation process, have been standardized, giving teams less freedom to block the air from the tire wake from entering the underfloor of the car.  This should create a less disturbing wake for a car that is trying to overtake, but it will increase the drag coefficient of the cars.

Bargeboards on the 2017 Mclaren MCL32

Further down the side of the car, the bargeboards help direct air down the side of the car towards the rear wing as well as create a vortex in the underbody of the car.  The vortex traps the air in the underside of the car, forcing the air to move faster down the underbody, as it is stuck in a confined space. Faster moving air creates a low pressure zone; combined with the higher pressure above the car from the drag produced by the wings and the bodywork, the car is pushed downwards, creating what is called “ground effect downforce,” helping the car grip the tarmac.  For 2019, the bargeboards will be lowered, preventing them from catching as much air as before. As a result, the cars should be slightly slower around corners next season.

2018 Red Bull RB14 rear wing with horizontal gills.

Finally, the rear wing endplates will be simplified, with horizontal gills banned for 2019.  While the pressure difference between the air over the rear wing and the under the rear wing generates downforce similar to the ground effect, the air over the rear wing builds up and spills over the top of the wing, creating a vortex.  This unintended vortex creates drag, as slowing air’s backwards movement and translating it into horizontal movement slows the car’s forward momentum. The current fix to the problem is horizontal gills, which create their own vortex in the opposite direction, cancelling out the effects of the other vortex, keeping the airspeed velocity off the back of the rear wing.  However, the two combating vortices highly disturb the airflow of the bodywork of the car behind, reducing overtaking. With the gills banned for next season, overtaking is further eased at the expense of drag.

Whether or not the 2019 aerodynamic regulations will make Formula One more exciting comes down to the effectiveness of the changes at creating less disturbing wakes behind the cars.  While the cars may be slower, the effects should be difficult to notice on television, and the new innovations to overcome the handicap of the regulations should mix up the order of teams on the grid.  To catch a glimpse of the fastest cars ever before it’s too late, watch the Brazilian Grand Prix on November 11th at 12:10 on ABC and the Abu Dhabi Grand Prix on November 25th at 08:10.