Aerodynamics: innovations increase efficiency

› New ŠKODA FABIA has lowest drag coefficient within its segment with a cd of 0.28
› Cooling shutters with active slats regulate air supply in the front bumper’s lower air intake
› Aerodynamics have largely been developed using virtual fluid dynamics simulations

Thanks to a host of ingenious aerodynamic details, ŠKODA has significantly reduced the new FABIA’s consumption and emission values. Compared to its predecessor, the FABIA’s drag coefficient (cd) has dropped from 0.32 to 0.28, making it the most aerodynamically efficient small car in its segment. The aerodynamics have predominately been developed using accurate CFD (Computational Fluid Dynamics) simulations.

Aerodynamics, a sub-field of fluid dynamics, describes the interaction between the air and solid bodies moving through it, and plays an increasingly important role in automotive engineering. The more aerodynamically sophisticated a vehicle is, the lower its drag. The energy required for locomotion is reduced, and fuel consumption and emission levels are lowered. In addition, good aerodynamic properties also have a positive effect on the handling of a vehicle. The aerodynamics have been improved using what is known as CFD simulations. Within approximately three and a half years, the ŠKODA engineers computed more than 3,000 of these fluid dynamics simulations. The result? With a cd of 0.28, the FABIA has the lowest drag coefficient in its segment.

The addition of a new type of cooling shutter has been an important measure. These shutters are actively adjustable slats in the front bumper’s lower air intake. When there is little need for cooling, they close automatically, thereby improving the car’s aerodynamics. This results in fuel savings of up to 0.2 l per 100 km when travelling at a constant speed of 120 km/h. To allow for a high level of cooling or to accommodate short stops, the system opens the shutters so that the maximum amount of air can flow in.

Approximately one third of a vehicle’s overall drag is caused by turbulence at the rear. That is why the new ŠKODA FABIA has a larger roof spoiler and side finlets that optimise the air flow at the rear. These components are made of plastic and can be manufactured very accurately. Specifically designed aerodynamic wing mirror housings reduce drag and direct the air flow to the rear in a targeted manner. At the front, the air is guided to flow through vents in the front bumper, known as air curtains, in a particularly aerodynamic manner close to the side of the body and the wheels. As the wheels alone generate around 25 per cent of the drag, ŠKODA is now also offering wheels with aerodynamically optimised plastic inserts for the FABIA – this is a first for the model. Twelve panels now cover a larger part of the underbody instead of three, especially in the areas that are crucial for aerodynamics, such as the engine bay and the axles.