In the era of the homologated, or so-called ‘frozen’ engine, it is easy to forget that there are still fruitful avenues of development and gain open to the manufacturers. Chief among these is the evolution of the fuels and lubricants used within the engine, which remain areas of cutting-edge technical research and development for partners such as PETRONAS.

Furthermore, when the MERCEDES GP PETRONAS team was newly formed for the 2010 season, it marked the beginning of a new technical relationship and the start of a race against time to demonstrate the companies’ shared technical expertise and cooperation, by developing entirely new fuels and lubricants for the Mercedes-Benz 108FY engine. This is how it was done…

What was the development process for the PETRONAS Formula One lubes and fuel?
PETRONAS Formula One fuels and lubricants are developed by an in-house R&D team based both at the company’s headquarters in Malaysia and at its lubricants facility in Turin, Italy. The first MERCEDES GP PETRONAS development lubricants were evaluated at Brixworth in January 2010 and introduced at the Spanish GP in May the same year. This was followed by the evaluation of MERCEDES GP PETRONAS’ development fuels in August 2010 with a race-worthy candidate identified from a series of formulations at the end of September. This fuel was durability-approved on the engine dynos, prior to being track tested for the first time in November at the Abu Dhabi Young Driver Test last year. Development continued in parallel, and the finally the best candidate was selected and introduced at the Malaysian GP last April. Since then, development has continued unabated and a further iteration if planned for the inaugural Indian GP, aimed at optimising performance for the ambient conditions at high-temperature events.

The rules state the fuel should be “composed of compounds normally found in commercial fuels”. How different are road-going and Formula One fuels?
A road fuel generally contains five or so moderately refined ‘complex’ components, to balance performance with affordability. A Formula One fuel, on the other hand, is blended from between 20 and 30 ‘pure’ (in other words, heavily refined) components. This gives close control of the final product specification and the performance it delivers. In a Formula One engine, the estimated difference in performance between the two would be over two per cent. Current Formula One fuel must also contain a minimum of 5.75% of bio-components, in line with existing European road-going fuel specifications. The inclusion of these components offers a power advantage because they are oxygenates, and increasing the oxygen in the air-fuel mixture can improve performance – but at the cost of increased fuel consumption.

What are the areas for further development in terms of fuel?
Both fuel and lubricant specifications can influence car performance according to a number of parameters. Among these are mass fuel consumption (GFC, or Gravimetric Fuel Consumption); volumetric fuel consumption (VFC); engine power and ambient conditions. Reducing GFC can lower the car’s race starting weight, or allow the engine to be used more aggressively for longer periods of the race; reducing VFC can improve packaging by permitting a smaller fuel tank; increased engine power reduces lap time; while fuels can also be designed to reduce the engine’s sensitivity to changes in ambient conditions.

What is the role of the oils used in the car?
Distinct PETRONAS SYNTIUM engine oil and PETRONAS TUTELA transmission and hydraulic oils are used in the car. We have the aim of introducing a new engine oil every race season, a target that has been exceeded since the beginning of 2010 in partnership with PETRONAS. The typical lead time for development and approval of engine and transmission oil is around nine months. In the engine, the oil must run as thin as possible to optimise performance; in parts of the camshaft, pressures can exceed 1.8GPa – which is equivalent to stacking more than 3,600 Empire State Buildings one on top of the other! The engine oil also functions as an engine cooling fluid, removing around 40% of the heat produced by the engine. In the gearbox, the oil must withstand shock loading (from gearshifts, of which there were over 4,000 in the race in Singapore) and be able to readily release air formed by the churning of gears.

How is the oil analysed across the race weekend?
Like blood analysis in a human being, oil analysis in a racing engine used to provide valuable information on its health. The oil gathers the wear debris of the various engine components, plus the by-products of combustion. Multiple analyses are conducted on an engine during the approval stage, before it runs on track, to determine its wear characteristics. During the race weekend, analysis is restricted to a technique called Optical Emission Spectroscopy, which details the metal content in the oil. Samples are drawn from the oil system after each practice session, qualifying and the race, then analysed. Comparing the results with a baseline sample allows the wear rate of various metals to be tracked with respect to engine mileage; the results also indicate the source of the wear, and enable preventative measures to be taken if necessary.

Source: Mercedes GP