Hyundai and Kia have unveiled Active Air Skirt (AAS) technology that minimises the aerodynamic resistance generated during high-speed driving, effectively improving the driving range and driving stability of electric vehicles.
AAS controls the flow of air entering through the lower part of the bumper, redirecting the turbulence generated around the vehicle wheels, adjusting itself based on car speed during high-speed driving.
In the EV era, competition to secure a better driving range from a single charge has become fierce, making the relationship between vehicles and aerodynamics even more important.
Aerodynamic performance has a significant impact not only on power performance but also on driving stability and wind noise. In response, manufacturers are exploring various measures to reduce the coefficient of drag (Cd).
AAS is installed between the front bumper and the front wheels of the vehicle and is hidden during normal operation, but activates at speeds over 80 km/h when the aerodynamic resistance becomes greater than the rolling resistance.
It then stows itself at 70km/h, with the difference aimed at preventing frequent operation in specific speed zones. The reason why AAS only covers the front part of the tires, is because it is more effective in improving aerodynamic performance that way.
This also functions to enhance downforce of the vehicle, thereby improving vehicle traction and high-speed stability. AAS can also operate at speeds over 200 km/h. This was possible thanks to the application of rubber protection material on the lower part.
Using a Genesis GV60 as a test bed, Hyundai and Kia have reduced the drag coefficient (Cd) by 0.008, improving drag by 2.8 percent – adding 6km to the vehicle’s overall range.
“This technology is expected to have a greater effect on models such as SUVs where it is difficult to improve aerodynamic performance,” Hyundai VP and head of mobility body development Sun Hyung Cho said.
Parallel to this testing, Hyundai has added rear spoilers, active air flaps, wheel air curtains, wheel gap reducers and separation traps, to vehicles to secure competitive drag coefficients. The IONIQ 6 has achieved a Cd of 0.21 as a result.