Red Bull RB15 testing update
As people continue to focus on the Ferrari vs Mercedes battle throughout pre-season testing it’s easy to forget that there is another team who will be fighting tooth and nail for the 2019 Championship too – Red Bull Racing. You might also forget that the Red Bull RB15 now runs with a Honda power unit for the very first time. 
S-duct outlet on the Red Bull RB15 nose at pre-season testing
One of the most prominent features on the RB15 is the S-duct outlet at the top of the nose (highlighted in blue). Believe it or not, this is to help control the airflow underneath the car, which is arguably one of the most important jobs of today’s F1 aerodynamic departments.
The flow under the nose feeds the front turning vanes and then the underfloor, so the cleaner teams can get this airflow, the more performance they can extract from the aero devices rearwards of the nose such as the bargeboards, underfloor and finally the diffuser. However, the air hitting the front of the nose is often turbulent and can ‘roll’ around the sides of the nose, and flow underneath the car. Furthermore, the airflow between the lower surface of the nose, the inner face of the front wing pillars and the upper surface of the front wing (highlighted in blue below) can also be extremely turbulent. Overall, the airflow under the nose is a very ‘messy’ area and needs to be tidied up before it reaches the turning vanes.&n...