

The Mercedes W06 Hybrid has a largely evolutionary design with many major concepts carried over from the dominant W05 Hybrid. However almost all of the components have been refined in some way with many detail changes both visible and under the skin.

“It is an evolutionary process and this also includes the regulations themselves. Relative to last winter, these have remained reasonably stable into 2015. But this is certainly not to say that the cars we see take to the track in Jerez will be near-replicas of their predecessors. Some changes will be more visually obvious, of course, but the devil is in the detail. Beneath the covers there have been a raft of developments from both a chassis and Power Unit perspective – all aimed at creating a car that is safer, more efficient, more reliable and ultimately faster. With the Hybrid era still very much in its infancy, there is plenty of scope for innovation. The challenge at this stage is to find the key areas for performance gain based not just on what we have learned a year further down the line, but also on where there is room for exploring new and innovative sources of competitive advantage” Paddy Lowe told the press.



The front crash structure of the W06 sits a long way back from the leading edge of the front wing. It is though that Mercedes carried out a number of crash tests at Cranfield in an attempt to get the best possible nose and indeed may have more iterations on the way.



The Mercedes featured an interesting windscreen ahead of the cockpit at Jerez. These small perspex parts are common in F1, but the W06 Hybrid had a version fitted with small cut outs which may act as vortex generators to reduce the impact of the cockpit on the overall airflow over the car.



Mercedes has carried over the lower front wishbone concept from the W05 which blends the two legs together in a single shroud, vaguely reminiscent of a Tyrrell design of the 1990’s though that was on the upper wishbone.



A look at the turning vanes around the leading edge of the side pod on the W06. Note the small dimple on the side pod under the bridging section. This likely shrouds the outer part of the side impact structure.



The roll hoop duct on the W05 is relatively conventional for a 2015 car with a horizontal vane in the centre splitting airflow between the V6 engine (lower section) and a heat exchanger mounted above the transmission (upper section)

The roll hoop has a singe very small support behind the drivers head. This is a significant change from the 2014 design which featured two much larger supports. Losing material from the roll hoop is a key objective for many teams as it is a heavy component mounted at the highest point on the car.



A good look at the rear of the W06 Hybrid. Note the bi-plane monkey seat winglet.



Extensive flow vis runs at Jerez reveal a little about the airflow ahead of the side pod. Note the downward flow around the undercut.



The flow pattern is clear to see on the front wing endplate, which was being evaluated on the opening day of testing.

One interesting element of the W06 Hybrid that cannot be seen is the fuel and lubricants used. Remarkably Petronas used the same specification fuel for the duration of the 2014 season, and has now introduced a new formulation for the 2015 season which it intends to use all year. Other fuel suppliers regularly modify their products for F1. The new fuel is claimed to enhance protection of the engine, provide better combustion and improves driveability. The fuel prevents engine damage by cleaning and protecting the critical high-pressure direct injection system and sensitive engine parts.

A new set of lubricants has also been introduced but may not be used by both Williams and Force India. With its increased power per litre of displacement, the 1.6 litre Internal Combustion Engines of the Hybrid era also run hotter than the 2.4 litre V8’s. This requires lubricants that do not get too thin under high temperatures and resist oxidation – balanced with a requirement to minimise friction within the ICE for reduced fuel consumption. The engine oil must therefore possess distinct thermal characteristics to withstand higher operating temperatures and cylinder pressures, and be optimised to effectively contribute to cooling. The use of Energy Recovery Systems (ERS) also brings the challenge of heat dissipation, requiring an ERS fluid that cools the system effectively. Equipped with a unique formulation to defend against extreme temperature and maintain optimum engine performance.

During the course of the 2014 season, Petronas upgraded its on-track chemical analysis to gain greater insight into the changes occurring in the oil within the engine under extreme conditions –crucial to the demands of adhering to a limited quantity of units per season. As a result, a new engine oil has been formulated that is undergoing testing with the option for adoption during the 2015 season.



(2014 Mercedes power unit)

Mercedes has made a substantial number of changes to its power unit, which is now called the PU109B Hybrid. Indeed Andy Cowell of Mercedes HPP has gone so far as to say “there is hardly any carry over, this is an all new power unit.”

We have been working hard on all areas of the Power Unit to increase the conversion efficiency of every single system – trying to make our package more thermally efficient and produce greater absolute power. The focus in this respect has been on combustion efficiency and frictional losses – be they in core parts of the ICE or the ancillary aspects of both ICE and ERS. There is very significant scope for change under the regulations and significant opportunities to make performance gains, so we have left no stone unturned in our quest for performance – and I am sure that exactly the same is true of our competitors.

The new Mercedes power unit features a slightly larger plenum compared to the 2014 version, to accommodate the new variable inlet trumpets, something that is claimed not to have caused any great packaging issues. Meanwhile the V6 engine features an entirely new exhaust concept, which seems to have done away with the pulse converter concept seen on last years power unit and adopting a more conventional layout.



THE CONCEPT OF MERCEDES EXHAUST LAYOUT IS DETAILED IN RACECAR ENGINEERING, ALONG WITH DETAILS OF WHY THE 2014 CAR WAS SO DOMINANT. READ IT NOW.

