- Improved Ford Focus aerodynamics help to reduce drag, cutting fuel consumption and CO2 emissions
- Streamlined new shape reduces drag coefficient by up to 7.8 percent, compared to current Ford Focus models
PRETORIA, South Africa, 19, 2011 – The all-new Ford Focus is due to be launched in South Africa in the coming months. The newly designed model achieves significantly improved aerodynamic performance, cutting drag by up to 7.8 percent to help reduce fuel consumption and CO2 emissions.
After spending nearly 1,000 hours in Ford’s Aerodynamic Wind Tunnel in Merkenich, Germany, the soon-to-be-launched Focus has an impressively streamlined shape and is one of the most aerodynamic vehicles Ford has ever produced.
The reduction in drag was achieved not only by detailed optimisation of the vehicle design but also by the adoption of innovative technologies..
Streamlined shape reduces drag
With its lower roofline and sleek, dynamic profile, the new Ford Focus has an innovatively streamlined shape. Compared to the outgoing model, it also has a notably ‘faster’ windshield angle, which adds to its aerodynamic advantage.
With careful optimisation of aerodynamic details, it was possible to achieve a significant 7.8-percent reduction in aerodynamic drag compared to the current Focus model. The new Focus hatchback has a drag coefficient of 0.295, compared to 0.318 in the current model.
The optimisation work was carried out by a combination of wind tunnel testing and analysis using extremely powerful computational fluid dynamics simulation tools.
During the wind tunnel testing, the vehicle is positioned in the centre of the tunnel, facing a giant fan, with its wheels on pads which measure the forces being applied to the car. The car can be turned to different angles to measure yaw moment coefficients.
The whole room is acoustically-treated and, with the giant fan turned off, is eerily silent. This is vital for taking wind noise measurements. An ‘Acoustic Mirror’, which looks like a large satellite dish, is used at the clay model stage to scan the surface of the car and measure the sound coming from it as the wind passes over and around the body.
Detailed features enhance aerodynamics and stability
Aerodynamic performance was enhanced by detailed development in all areas of the vehicle. To prevent unwanted drag, the front end was completely sealed using a hood seal and shielding beneath the engine, allowing air to be ducted efficiently via the grille to the cooling pack. Airflow beneath the car is managed by tailored panels on the underbody, with a lower front deflector and speed lip, engine undershield and front-wheel deflectors.
On the sides of the vehicle, an optimised mirror design reduces drag while also minimising wind noise and managing the flow of rainwater along the side glass. The A-pillar was carefully shaped, incorporating a special moulding to further reduce drag and minimise wind noise.
At the rear, airflow under the vehicle is managed by a diffuser integrated with the bumper moulding, while an additional undershield contributes further drag reduction. Integrated rear spoilers help to minimise drag and enhance stability, while subtle features added to the sides of the rear-lamp mouldings provide a sharp edge, which allows the airflow to separate from the body sides in exactly the right place.
“There are so many small features like this around the car and they all work together to give a very low overall drag coefficient,” said Manfred Lentzen, supervisor, Aerodynamics Development. . “We have really made a big improvement versus the current model and versus the competition.”