Features - 2010 Grand Prix Review
FEBRUARY 10, 2011
Williams: Back into the top 50%
The 2010 season saw Williams back into the constructors championship top half for the first time in three years - eighth in 2008, seventh in 2009 and sixth this time was indicative of forward progress even if the team is not the force it was in its halcyon days of the '80s and '90s.
It was a close-run thing. Williams beat Force India to sixth place by 69 points to 68, with Rubens Barrichello pipping Adrian Sutil by just half a second in the season finale in Abu Dhabi. They were 12th and 13th respectively so ultimately didn't score, but had there been any contact up front, not unlikely a championship showdown, sixth place was on the line...
"The big change for us was the Cosworth engine," says technical director Sam Michael. "We had a pretty busy time packaging it and changing the gearbox and back of the chassis to suit. Not having engine continuity going into a year with no refuelling made it difficult to size the fuel tank. Actually though, the amount of fuel we had for the highest consumption track was within 0.5kg of the tank capacity, so we got it bang on and a lot of effort went into that. We achieved it by looking at Cosworth data from 2006 and by looking at the brake-specific fuel consumption they had on their dyno and comparing them."
The team made its FW32 longer rather than wider to avoid pushing the radiators out, making the sidepod undercut too small and losing downforce. They were shortish in terms of wheelbase between the back of the chassis and rear axle but not in terms of overall chassis length.
"It was just because the gearbox was short," Michael explains. "It was very different from the transmission used with the Toyota because the clutch moved from the engine to the gearbox. That changes all the clutch actuator and hydraulic system and also the vibrations on the gearbox and engine."
In terms of the 2010 season's innovations, Michael admits that Williams did not think of an F-duct but did consider an exhaust blown diffuser.
"The first time we saw an F-duct one was in February and most teams brought them in at the same time," he says. "We never considered that the driver wasn't part of the car. That's key to the interpretation, which could have been challenged, but wasn't.
"We had a hole beneath the driver's leg and enough positive pressure inside the cockpit to stall the rear wing -- we saw that from CFD. So, the driver drove along with his left leg over the hole, sealing the duct, then when he went down the straight he moved his leg off it and the air flowed through the hole and through the chassis to the engine cover spine to the slot on the rear wing, which stalled. It was quite simple and we didn't need to take any feed ducts from outside. The positive cockpit pressure was plenty. As soon as the driver pulled his leg off he could feel it trying to be sucked back down.
"The downside was that the driver had to keep it sealed all the time. For Rubens (Barrichello) it was easy because he's a right-foot braker but for Nico (Hulkenberg), if he had to brake really hard his leg could come off the hole and unstall it. It took him a while to get used to it. We had to re-do his seat three or four times.
"The blown diffuser we did think of, which was really annoying. We had it in our tunnel in October 09 but because we changed engines we didn't have an exhaust system and had to release one around November for the start of the season. Because we had a lot of loading on the design office because of the engine change, we postponed that project and put it on the back burner.
"We said, right, let's get out a top exit exhaust because we didn't have enough confidence to just go with a blown diffuser. We had no idea whether the temperatures would be insane and whether we could cope with them. If you look at what Red Bull did, that's exactly what we would have done. They did three tests with a top exit exhaust and only then tried a blown diffuser at the last test, so had a solid back up. If they'd roasted the car, they could just have gone back to the top exit.
"The exhaust programme is completely integrated with the bodywork and aero programmes, so it gets quite complicated. We were on it straight away after we saw Red Bull run it. That's why when we did bring it to the track it worked straight away -- we knew immediately to blow straight into the diffuser. There were a couple of teams that even late into the season didn't blow into the spat.
"On both our car and the Red Bull, the closer you can get to the tyre the more downforce you can get, but it's a matter of getting out there without burning the tyre. As soon as you have car speed it's fine, but the worst condition is when you're at a pit stop or on the grid. The plume is coming outboard and if it starts to heat the side of the tyre you risk a failure. We spent a lot of time tuning that."
The team also had to consider the mechanical side. They used PyroSic panels on the floor for heat resistance, with a set of panels for the first diffuser coming in at €25,000 per floor! "When we developed the plume and got confidence in it we got that figure down massively, to about a tenth of the original cost," Michael explains, "but at first we used PyroSic everywhere!"
Williams found its downforce from the blown floor to be 100% consistent and using engine mapping to improve it, which they did from Spa onwards, made a big difference.
"Once you started using it in braking as well it was better again -- an even bigger step than the initial floor," Michael explains. "You got downforce everywhere and there was no change between on and off throttle. Cosworth spent a lot of time on the dyno doing that. The job they did was impressive because we went out at Spa, first lap in all those wet sessions, and it just worked straight away. Both drivers said, "We're racing this, for sure!"
In terms of in-season development Michael admits that Williams' rivals took a bigger step around Barcelona, where everyone tends to make their first significant post-flyaway aero updates.
"Our real turnaround was Montreal," Sam says. "The car was more competitive. We changed the aero package vey significantly for there and that changed our direction. We changed how we developed the car and in terms of philosophy it was quite a big change.
"Rubens is very good at feeding back what the problems of the car are. When you bring developments to the track and have him tell you exactly and very quickly what it's doing, that's quite important. He was exceptional from that point of view."
The team has promised a more aggressive approach to 2011 and with its small gearbox, low rear end and steeply angled driveshafts, the FW33 looks true to the team's word. It remains to be seen whether Williams can continue its forward progress in the tough fightback to the front. Fifth place in 2011 could be a big ask with a rookie, this time in the shape of Pastor Maldonado, partnering Barrichello.