Scuderia Toro Rosso (STR) launched their car on the first day of the Valencia test. It’s significance has been somewhat lost amongst the fanfare of the front running teams cars and the innovation of the midfield runners. However the new STR06 deserves more attention, as it has some unique aerodynamic concepts that are drawing praise from other teams engineers. STR have been able to reduce the cooling and packaging demands placed on the sidepods. Thus with a smaller sidepod envelope, the team have revived an old concept from Ferrari, the double floor. This separates the sidepod from the flat floor of the car to improve airflow towards the rear. Pioneered by the Jean Claude Migeot while at Ferrari, the twin floor concept came about in 1992 for the teams F92A. Although not a success, mainly due to mechanical reasons, the car did exploit clever sidepods to improve flow over the diffuser.
Diffusers are limited in length and exit height, as such there is little that can be done with their internal geometry to create a greater volume for more expansion-ratio and hence more downforce. Teams realise that driving more airflow over the diffuser not only creates higher pressure above, but can also drive airflow within the diffuser with aids such as gurneys on the trailing edge of the diffuser opening. The problem is getting airflow with enough energy to pass over the diffuser. To reach the diffuser, the air has a tortuous journey. Starting with passing over the front wing, under the nose and raised chassis, then over the splitter and around the sidepods, before sweeping in between the rear wheels and through the rear suspension. We’ve seen other solutions aimed at improving this path, such as the extreme raised nose, tight coke bottle shape and recently the undercut sidepod. It is the sidepods that create the biggest obstacle to the airflow, sidepods span some 30-40cm beyond the sides of the chassis and in order to package large enough radiators they tend to need the full width across a significant height, making the sidepods effectively a rectangular block to the airflow. If you could remove some of this blockage, especially low down then the airflow can head unimpeded to the diffuser. This is exactly what Migeot did with the Ferrari F92A and Ascanelli has done with the STR06. The Toro Rosso’s sidepods curl in backwards towards the monocoque along their full length, this space is evidenced by the large area of flat floor beneath the sidepods. Air passes under the sidepods directly to the diffuser with little to sap energy from the airflow.
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Scarbs
