Due to customs regulations and the 3 days that separated the end of the Japanese GP and preparations for Russia, there were few technical developments brought to the new Sochi circuit.
It is for this reason that whilst we will still look at the minor changes seen on a few cars last weekend, this post will mainly analyse why McLaren appear to be getting on top of things and beginning to move forward in recent races.
You could say that McLaren should have been challenging for a title this season, but in reality it was always going to be a year of recovery and learning. 2013 was the worst season in their history and once we knew that the team were switching to Honda power for 2015, 2014 became a year of transition.
It has been an up-and-down 7 months so far but I genuinely believe McLaren have a much better understanding of how their car behaves – particularly aerodynamically – now than a period about 3 years ago. We all know McLaren have lagged behind others in front wing design for numerous years but 2014 saw a change in philosophy, which continues to progress even up until Russia.
In recent years, the Y250 axis of the car (where the neutral section of the front wing joins the main plane and flaps) has been exploited by generating powerful, elongated vortices to offset front tyre wake and seal the frontal portion of the floor at least. We have seen this section change in shape numerous times due to the teams’ understanding of vortex production in this area and tuning the vortex around the characteristics of the tyres under load.
In Russia, McLaren added metal fixings to the Y250 join point, clasping the leading edge of the wing to reduce the amount of flex under load. We first saw them testing this new development in Singapore, where the nose cone hosted a camera which monitored a number of points on the front wing endplate to track the flex of the wing. With this data gained, the team may have even adjusted the stiffness of the clasps (presumably made from aluminium, or perhaps titanium) before Russia to get the desired flex across a specific load threshold.
The advantage of using these clasps revolves around the production and steadiness of the Y250 vortex and, by reducing the amount of flex, could potentially increased the consistency of it at high speed or over bumps and kerbs. It is no secret that McLaren run a very stiff mechanical setup to make good use of their aerodynamic platform: understanding how the front wing interacts with the mechanical balance of the car undoubtedly helps create a more consistent car at least, aiding driver confidence. Producing a better, more stable vortex also helps seal the floor more easily, which in turn allows a higher rake angle which extracts more rear downforce from the diffuser. The beauty of the front wing is that it has a trickle-down effect although this can also hurt you if you get it wrong.
Understanding these minor flow structures and their interaction with the mechanical setup of the car has risen McLaren above Force India and arguably ahead of Ferrari in terms of performance. Like the team have constantly said this year, there is nothing fundamentally wrong with the MP4-29, it’s a culmination of detailed aspects which separate it from the top tier. We may not see a McLaren reach the top step (or indeed any step) of the podium this year – unlike what Ron Dennis insisted some months ago – but there are winds of change. If Fernando Alonso joins next year and Honda produce a good powertrain, it won’t be long until we see them back once again.
Along with recent aero updates, Toro Rosso have also found new ways of managing rear tyre temperatures and the way the tyres interact with the heat generated from the rear brakes. Seen in Russia, the rear ‘cake tin’ hubs were lined in a gold-coloured foil. Often teams will use a gold alloy foil to surround certain elements of the engine, such as the exhaust manifold, to reflect heat – up to 78% of that radiated from the surrounded component.
Surrounding the hubs in this foil will actually retain the heat within the assembly, increasing rear brake temperatures rather than allowing the heat to expand into the rims/tyres. As the rear brake discs are far smaller this year than in previous years gone by – due to the regenerative capabilities of the MGU-K in 2014 – they are quite temperature sensitive as the brake pressure varies during the braking phase as the ERS harvests energy. Toro Rosso must clearly feel that isolating most of the heat energy from the brakes is beneficial for rear tyre preservation and managing temperatures when preparing for a qualifying lap. As we saw with Valtteri Bottas, if the tyre overheat towards the end of the lap the rear end will simply give up, so the gold foil is a logical solution to this sort of problem.
Sorry that this week’s Tech Highlights are short, but unfortunately these are the only real developments we saw! McLaren will bring a large update to Abu Dhabi so the teams are continuing deep into the year, which is peculiar considering the new nose regulations for next year. I will have some more feature posts up as the season draws to a close (and over winter) and then hopefully some more inside stuff on Formula Student.