Patrick Head

THERE HAS BEEN RECENT PRESS ON THE PROPOSED NEW Formula 1 chassis rules for 2013 to go with the already FIAapproved engine/driveline rules. These laffer rules specify that the engine will be an ‘inline’ four-cylinder of 1.6-litre capacity, with the cylinders along the axis of the vehicle, and a single turbocharger integrated with an energy recovery system (ERS) of 120kW (approximately 160hp) maximum transfer rate, in or out.

The most notable factor however, is the limitation of a maximum fuel flow rate of 100kg per hour, and in the proposed chassis rules an allowance of only 100kg of fuel for the same length races as in 2011 (usually just over 300km), down from about 150kg in 2011. The chassis proposals have been on the basis that lap times should be no more than five seconds a lap slower than in 2010.

Recently it has been suggested that the current 2.4-litre V8s should be permiffed to continue in 2013, with an equivalence formula. In my view the fuel limitations will make this very difficult, as with the high engine speeds, these engines would almost certainly require more fuel. ‘Equivalence’ has never been successfully applied in motor sport; always one route or the other is favoured.

Chassis rules are yet to be approved, but time is running short. The FIA conducted a study in which I participated along with Rory Byrne of Ferrari and others, which in order to meet the drag and downforce coefficients predicted by simulation proposed a car with shaped-underside sidepods and small wings. But the teams are concerned about stepping so far from current experience and possible runaway downforce development, and countered with a proposal for a car closer to 2011 Monza spec, retaining the ‘step plane’ flat boffom with a diffuser starting at the rear axle centreline. Recently there have been, from Bernie Ecclestone and Ferrari in particular, concerns expressed about the acoustics of a turbo four and whether that configuration sufficiently represents their products. But with motor magazines full of hybrids, electric

vehicles and low CO2 emissions, I personally think that Fl should lead rather than follow. The 1.6 four-cylinder turbos are predicted to peak at about 630hp, to which should be added 160hp from ERS (although not always available), so as long as the Hamiltons and Alonsos are driving them I see no lack of interest. We shall see!

A topical maffer in Fl 2011 is the location and timing of exhaust gas blowing to aid aerodynamic performance, and we see from Renault and Red Bull two very different successful applications.

Renault run the exhaust tailpipes forward to exit sideways at the front of the sidepod (above), while Red Bull, in a route followed by other teams including Williams, direct the exhaust rearwards, wide on the diffuser edge which influences flow at the leading edge and side of the tyre and under the diffuser. The complex interacting resulting flows are only really predictable using computational fluid dynamics (CFD), which is a powerful tool but is not yet making wind tunnels redundant.

Of particular interest is what is happening ‘off throffle’ when the driver is braking hard and entering a corner. For some time the FIA has required that the driver pedal position should relate in a consistent manner to the torque produced by the engine, rather than to the actual engine throffle positions, so to maximise exhaust velocities when braking teams have been opening the engine throffles wide (100 per cent) and shutting off ignition and fuel, even though the pedal position is at zero. This has been referred to as ‘cold blowing’, which becomes ‘hot blowing’ if some fuelling and ignition is added, possibly with ignition retard to keep torque levels within limits. This is, in effect, using the engine for strictly aerodynamic purposes at this time, and whether this truly fits within the current limitations of the technical regulations is to be debated at a Technical Working Group meeting after Montreal on June 16, so we’ll know the outcome by the time you read this.

There is always something controversial and of interest in Fl!