LOOKING TO MAKE A DENT
The edge of the floor has been significantly dented at sidepod level, which is quite original as well (see white arrow).
The rationale is roughly the same as the floor slots ahead of the rear wheels (yellow arrow): allowing the high-pressure air above the floor to go under the car in order to seal the edges of the diffuser, thus protecting it from the dirty wake of the rear tyres.
Sealing the diffuser’s edges is all the more important this year with teams running higher rake angle on their cars. Red Bull has been a pioneer in this area so its does not come as a surprise to see the philosophy applied to the RB13.
Raising the diffuser is not without risk. First, a higher diffuser is more exposed: turbulent airflow can enter the low-pressure area laterally, which hinders the diffuser’s efficiency.
This is the reason why aerodynamicists generate a series of vortices to seal the edges of the diffuser as much as possible.
The large dents in the floor are working in conjunction with the bargeboards in order to protect the diffuser’s edges.
Secondly, teams must ensure that the splitter, which sits closer to the ground, does not get damaged, nor wear out beyond the mandatory limits.
Now, the splitter will be 100mm shorter this year, per article 3.16.6 of the new technical regulations, which makes it more enticing to have a higher rake angle.
Such is the angle on the RB13 that the lower front wing endplate is curved to avoid rubbing the track.
The challenge lies in generating downforce both at slow and high speed, i.e. with different ride heights as these change according to load. Hence the important role played by the hydraulic pitch control systems fitted on several cars, which has come under greater scrutiny from the FIA over the winter.
Some believe the Red Bull's system could be under threat but team boss Christian Horner insists the car is compliant with the latest technical directive on the matter. That said, there could well be more twists to the story at the season-opening Australian Grand Prix.
