Petrucci explains the Toro Rosso STR5 aerodynamics

Nicolo Petrucci, Toro Rosso Head of Aerodynamics

"Having only taken over the wind tunnel in Bicester last year, our efforts were not only directed towards defining the 2010 car, as the main impetus was aimed at setting up a department and a structure that would be used to design the Toro Rosso cars of the future. The 2009 car was used as a reference point in our work in the new wind tunnel to understand it better."

"The development of the Bicester facility is a long-term project as improving and getting the most out of a wind tunnel is a very lengthy process. We have started by building up a team of people, who are working on STR5, but more importantly thinking about the long term, and currently I believe we are working in the right direction. Our philosophy in the tunnel is to work in the most cost effective and efficient way possible."

"In the short term, in the later part of this season, we should see some improvements to this year’s car, which will have been generated by the wind tunnel. This year’s car is a landmark for Scuderia Toro Rosso. The concept and development is all our own work, so it is the starting point of the real development of the team, not just in aerodynamic terms. I hope we will see a gradual improvement during this season, but the real step forward will not be visible until 2011 and 2012. The wind tunnel is crucial of course, but we must not forget the CFD (Computational Fluid Dynamics) group and the Calculation side of the project. We are using one of the most advanced CFD codes and we have put together a group of people with great experience, not just in aerodynamics, but in terms of developing the actual CFD."

"The STR5 was designed taking into account the major rule changes introduced for 2010, most significantly the need to accommodate a much larger fuel cell. In addition, the different dimension of the front tyres has an effect on the front end of the car and also the rear, which is affected by the wake of the aero effect at the front. We tried to put together a package that is relatively conservative. This was because we only took on the wind tunnel last summer and most of the work involved setting it up, commissioning its equipment and the car model for use in the tunnel. This work was not completed until the end of 2009, which means that, so far, very little time could actually be devoted to the aero development of STR5."

"The new tyre rule called for a redesign of the front wing and it also has an effect on the side pods and barge boards. At the time of launching the new car, the front wing was not very different to the one last used on the 2009 car. However, apart from that, the car is completely different to STR4: the chassis, rear suspension and all the main characteristics have been affected by the rule changes. Our primary concern was to ensure that we could run the car efficiently and without problems in the first few races, because we are still very heavily involved in developing the wind tunnel and our CFD programme. Initiating both these programmes at the same time was a real challenge."

"As always in F1, there are compromises that have to be made with the aerodynamics. It depends on how much time you have, the amount of wind tunnel time available and the calculation power available to you. One has to take into consideration the mechanical aspect of the car and the cooling requirements, for example of the engine, gearbox and other components. The teams that were very successful last year were those that, in some cases, had been developing the perfect concept for over a year. That is definitely not the situation for Scuderia Toro Rosso at the moment, but we have a clear idea of how to progress in the future and we have employed around 30 people in England and Italy, to work in CFD, calculation and in the wind tunnel."

"In terms of how the various areas come together, for every part of the car, you can start with an idea and a concept. Next comes the calculation work with CFD, the production of prototypes for the wind tunnel and then these two activities move forward in parallel. One looks at the implications in terms of the actual structure, for example of the nose and the crash structure, the suspension and the gearbox. The more the job evolves, the closer you get to the right compromise between all these elements. If at the end of the job, you have come up with something different that brings a performance advantage, then you have reached your goal."

"The relationship between the wind tunnel in Bicester and the staff in Faenza is very important. All the people who work on experimental activity need to work together closely. Teamwork is vital and the people need to be able to communicate with one another on an almost hourly basis. The rest of the department, working on CFD and calculation are based in Faenza, but they can see the results from the wind tunnel in real time. The same goes for the group in Bicester, who can see the result of calculations as soon as they come out of the computer. In the era of modern communications, it is not a hindrance to have the wind tunnel in another country. Having a technological island in the UK, which is at the centre of F1 technology, is a big advantage for Scuderia Toro Rosso."

"The programme allows for around 2,400 hours of wind tunnel use a year, which is well within the restriction limit agreed among the FOTA teams."

"Our philosophy is based on efficient development and production processes based on the high quality of the aerodynamic concepts we investigate."