Suggestions that this year's F1
rules would make cars more similar have been scotched by some interesting
innovations in the pitlane - so what are the key design trends of 2011?
This year, the regulations banning double diffusers and changing tyre manufacturers appear to have forced teams to push the innovation boundaries more than ever to find that crucial extra few tenths of a second. Indeed, Williams technical chief Sam Michael admitted recently: "This is the most standardised set of regulations Formula One has ever had but the cars look completely different..."
One of the most significant design focus points has been the need to reduce the blockage to the rear wing as much as possible, to maximise downforce at the rear end and limit the downforce-reducing effect of the double diffuser ban. This has been achieved by sculpting sidepods to have large undercuts at the front and strong downswoops at the rear and, in many cases, by using the Red Bull approach of a much more compact pullrod suspension system rather than traditional pushrod solution. There have also been many different innovative approaches to maximise the benefit of using blown air from the exhaust within that diffuser system.
The return of KERS (never banned but just unused due to a gentleman's agreement in 2010) has contrasted with this, as the need to keep the unit's heavy components (batteries and motors) as low to the ground as possible requires space in the sidepods, so a compromise has had to be made in some cases. Meanwhile, there have been several different approaches to the activation of the other new overtaking aid, the movable rear wing.
The other major change this year is in tyre design, with Pirelli opting to design a tyre that degrades much more over its short life than the Bridgestone rubber. The aim is to increase the number of pit stops and the amount of excitement generated in races. To limit the chances of someone 'lucking in' to the right balance to best manage the tyres, the teams agreed to a fixed weight balance range but despite this the change in tyre behaviour will still have its effects, both in terms of performance and in the strategic planning of races.
Below is a rundown of the main technical issues this year:
Single diffuser: The ban on double diffusers has created significant reduction in downforce from the floor and rear end of the car as the amount of downforce is proportional to diffuser exit surface area. Teams have worked hard to recover this by opening up airflow into the lower rear wing by lowering the rear of the sidepods and gearbox and also creating undercuts to the sidepods to steer air into this area. However, aerodynamic sensitivity becomes greater with a single diffuser and managing that could be significant this year.
Undercut sidepods: The aim of this is to make it easier for 'clean air' to flow into the rear section of the sidepods, and teams have taken this approach to varying extremes. The scalloped shape helps encourage 'clean' air to flow from the area under the front chassis section, behind the raised nose, around the sidepods - and with more 'clean' air going into the diffuser section there is more grip at the rear end.
High nose: Most teams have now gone for a dramatically high nose. This stems from the need for clean airflow over the car and the higher the nose the more clean airflow there can be under the car - because this is where that air comes from, and anything that gets in the way and obstructs the airflow makes it less efficient. However, the high nose comes with a compromise as it raises the centre of gravity and also forces suspension to angle acutely upwards because the wheels are lower relative to the locations of the suspension connection points. That could cause failures if parts are not strong enough to cope with the loads and it also may become a handling issue, as the movement of the suspension effectively tries to force the tyre outwards and if the grip from the tyre contact patch is low the car could slide.
Blown diffusers: To make the diffuser even more efficient and work even harder to produce downforce, Red Bull re-introduced the old concept of using exhaust gases to energise the flow in this area last year and this has been a main focus of many teams this year - with many different approaches. These range from the fairly standard approach of feeding exhaust air in at the rear of the car to more radical solutions where the exhaust exits in front of the sidepods and feeds exhaust air in as far upstream as possible. There remains debate over the ideal solution to this - but with such radical concepts in an area that has significant lead-time to develop, there could be some major winners and losers in this area of innovation.
Rear wing: The movable rear wing has been adopted by all teams, but with different operational solutions. The rules allow the bottom of the rear wing flap to be moved up 50mm, opening up a slot gap in the wing and dramatically reducing drag (estimated to be up to 10 times the reduction in drag achieved by the f-duct, which is massive). The rules governing the rear wing's operation in action are only pencilled in so far and could be changed if it is more or less effective than planned, but right now it is only allowed if a driver is within a second of the car in front, can only be used in an FIA-specified location on track and cannot be used in defence. Estimates suggest it will give an equivalent of a 100bhp benefit, making overtaking much easier.
KERS: This system stores braking energy and converts it into an 80bhp power boost for 6.66seconds per lap, and can be used at any time around the lap until it runs out. Not all teams will run it because it comes with compromises in terms of weight, bulk of equipment and cost, but with the minimum weight altered to compensate for it, all those who are serious will do. Ferrari, McLaren and Renault used their own versions of it in 2009 while Sauber also used it in their BMW guise but will not be using that same technology this time around (they will be using Ferrari's system). Those four are the only teams with prior experience of these systems, and could be at an advantage.
Tyres: Teams are all in the same boat in terms of managing the new tyres, but despite the weight distribution fix there will be some teams whose cars suit the new tyres better than others - be that by luck or good judgement. Also, drivers use tyres differently and some will be better than others at managing their degradation - which could be vital for success in 2011. This will be most noticeable in races where the conditions are on the edge, either when tyre temperature are hard to maintain (cool tracks) or when wear is extremely high (hot tracks), in which case small advantages could be accentuated.
Rear suspension: Red Bull's pullrod suspension approach offers a much more compact system compared to the bulky pushrod approach because the rockers for the suspension arms are mounted lower on pullrods than on pushrods. This reduces the blockage in the rear end around the diffuser, so is more aerodynamically efficient, and also puts the parts lower, so lowers the centre of gravity of the system which is important for overall car handling. However, the major drawback is that parts cannot be as easily accessed, so set-up changes are more difficult. Some teams have followed Red Bull's lead, while others - most notably Ferrari - have stuck by the pushrod system, but modified it to make that system more compact. With the new tyres set to cause confusion, at least in the opening races, the ability to change set-up significantly could be crucial - and if so, those with the traditional system could well be with a significant advantage.