Auto

The new BMW 3 Series - Wind tunnel

"Optimisation of aerodynamics and passive safety also takes place largely behind closed doors. At the BMW Before it can go into series production, the new edition of the sports sedan must first complete a programme of testing whose breadth and intensity far exceed the stresses and strains of everyday driving. Group’s Aerodynamic Test Centre in Munich, full-size vehicle models, prototypes and production vehicles are tested using precise reproduction of real-life airflow conditions on the road. At the centre’s wind tunnel, the new BMW 3 Series Sedan has been given the detailed touches required to bring its drag coefficient down to 0.23. The key factors here are not only how the car manipulates the airflow, the ideal channelling of air around the underbody and the optimisation of the spoiler lip at the rear of the body, but also details such as combinations of wheels and tyres. The introduction of the WLTP fuel consumption testing procedure has meant all the wheel variants available for a particular model have to be put through an extensive aerodynamics test. Every variant is checked to establish how the wheel design and tyre size impact on the aerodynamic characteristics of the new BMW 3 Series Sedan and therefore its fuel consumption and emissions. Differences in the stipulations for occupant protection applicable in different continents mean that several pre-production examples of a new model have to be deformed in a controlled process as part of crash testing at BMW’s Safety Centre. As a result, the new BMW 3 Series Sedan not only provides driving pleasure to customers around the globe, it also meets the full set of safety requirements to score top marks in all the relevant crash tests worldwide."