David Mart: It is all about assessing risk

Canadian Grand Prix technical feature

The Formula 1 World Championship departs from its European heartland for the first of two North American races in 2012.

Renault Sport F1 arrives in Canada off the back of three successive Formula 1 victories, the most recent being the jewel in the crown as Red Bull Racing’s Mark Webber blasted to his second win on the streets of Monaco.

His engine engineer, David Mart, took time out to explain the very individual characteristics of the Montreal weekend. Cooling, fuel consumption and pedal maps are the biggest points, plus monitoring the weather, which has become so changeable over recent years:

“In Montreal you can get nice sunny days in qualifying and rain arriving on Sunday, or rain on Friday and dry on Sunday. In many ways that is worse because trying to figure out dry fuel consumption when you’ve only had wet running on Friday is very tough.” he explains.

2011 Canadian GP: Mark Webber, Red Bull Racing and Lewis Hamilton, McLaren Mercedes

Photo by: xpb.cc

“In the rain the cars are running more slowly and using less fuel. In addition there is obviously more moisture in the air, so less oxygen is ingested into the engine and the fuel consumption is further reduced. One thing you can do going from a sunny Friday to a wet Sunday is reduce fuel levels, dependant on what your information is on rainfall.

“It is all about assessing risk, but if you are confident in your weather predictions then you could put less fuel in the car than you would need to finish a dry race. However running out of fuel is a potential risk; if the conditions change again and the track dries out, you could have too little fuel on board. Therefore, you need to estimate the highest fuel consumption based on the dry. It is all about confidence; if we are certain on wet conditions then you can ‘short fuel’; but you have to be certain, especially you have to fuel the car 45 minutes before the race starts!”

Another area that can be affected by wet conditions is the cooling configuration. “If the FIA declares the track wet for the race but it was dry for the qualifying, we can amend the cooling configuration of the car. When it rains, the engine generates much less energy to dissipate as the revs are much lower with lower average throttle times as the cars tend to circulate a bit slower. This all connected to the lower fuel consumption rate: with less energy going through the engine, there is less energy to dissipate.

“If you maintain dry running levels of cooling, it’s actually too severe for the engine and you will cool it too much – you need to bear in mind that we heat the engine up to 70 or 80°C water temperature to be able to fire up safely. In the wet the operating temperatures are much lower.” A further effect of the rain is on the handling of the car, and engine settings can also help in this regard. “When it is wet, the driver needs a bit of help coming out of the corners to control wheelspin. The use of pedal maps is critical so that the amount of torque is correct in those conditions. In the wet the map will be far more progressive in terms of application of power as you don’t want a sudden burst of torque or you’ll get wheelspin.”

One individual quirk of the Canadian Grand Prix is the track itself. The Circuit Gilles Villeneuve is composed of many different types of asphalt as different sections have been resurfaced at different times over the years. This, in itself, can cause set-up issues.

“It always makes it tricky when you have changing track conditions on one lap. You can’t always cater for that and so you have to find a compromise. It comes down to the relationship between engine and pedals and how much torque the driver needs. You’ll spend Friday determining how you are going to set that up.”

So a track whose surface changes sector by sector, and weather which can shift at any moment: the Canadian Grand Prix weekend therefore seems to be something of a compromise, particularly as the car enters parc fermé conditions after qualifying.

“If the weather conditions remain stable, it is far easier to find that sweet spot and for the drivers to find a point with the engine where they are happy. But if, as has happened over the last few years, the weather decides to play a game with us, then it is all about making the best of what you’ve got.”