The cars layout will inevitably be hit by the Pirelli tyres and mandated weight front to rear distribution. The weight will be shifted a few percent rearwards, this will provide the teams a chance to alter the cars layout, shifting the major masses towards the rear axle. Most likely the gearbox will be shortened, having been extended to maximise the double diffuser last year. So for the first time in several years, super short ‘boxes will be in vogue. Curiously USF1’s idea for super short transverse box, might be attractive for an innovative team.
Additionally the rearwards weight bias, no longer rewards super light and of course expensive carbon gearboxes. Although as with any part on an F1 car, lighter weight components simply create more ballast available for tuning the cars set up.
To maintain wheelbase, the teams can either extend the front of the chassis or extend the fuel tank length. The former will be good for aero and making the vanes around the front work more effectively. While the latter solution will be attractive as KERS will eat up crucial fuel tank volume.
In our Generic 2011 car (above) I’ve shortened the rear and extended the front, retaining the same wheelbase. To maintain Fuel tank volume, rather than mount KERS battery pack under the fuel tank, I’d suggest it goes in the right hand sidepod, as McLaren did in 2009. Sitting at floor level in the wake of the lower side impact protection beams, this should not impact sidepod volume or undercut. Albeit at a small cost in CofG height, as many teams will still prefer to fit the battery pack under the fuel cell, as the 10-15kg battery is denser than fuel the CofG is lower and the batteries safely out of the way. Also helping retain fuel volume, could be Hondas idea of mounting the Motor Generator on a series of gears, to shift it from the front of the engine and into the sidepod area.
With the KERS Power Control Unit in the left-hand sidepod, this needs an air inlet as the electronics are air-cooled. The Battery pack is water-cooled from its own pump and radiator in the right-hand sidepod. The Motor Generator is oil cooled from the existing engine oil system. The engines oil cooler is mounted atop the gearbox and fed from ducts either side of the roll hoop.
Also on the cooling side, the radiators reach right to the very front of the sidepods, nestling in the side impact protection. The also frees up sidepod\fuel tank space, and beneficially allows an extra cooling outlet at the front edge of the sidepod. One of the few legal areas for cooling outlets. Additional cooling outlets to the side of the cockpit and at the tail of the upper engine cover are used, as they vent hot air close the front of the sidepod, this reduces the sidepod volume required to route the air to the rear of the coke bottle shape. Slimmer sidepods force better airflow over the diffuser for more downforce.
Another aid to the flow over the diffuser is the shape of the gearbox. This is largely dependant on the teams philosophy, Red Bull reintroduced Pull rod suspension at the rear of the car. This is likely to be the much talked about shift in concept for other teams. Pull Rod is lower, but wider. Push Rod tends to be taller and narrower, but mechanically has a higher centre of gravity. I doubt there’s a significant gain from either system.
With either suspension system, the smaller “single deck” diffuser will not encroach into the volume taken up by the gearbox. Thus designers can make the gearbox and in particular the heavy differential, much lower. This creates a easier path for airflow to the beam wing and usefully lowers the CofG. However Red Bull took this approach in 2009 and suffered some driveshaft issues as the angularity of the CV joints was on the limit of their design.
A practice first exploited by Red Bull was the lowering of the rear wing endplates down to floor level. This is a loophole in the rules, as although the wing is narrower than the diffuser, the additional rear overhang increases the expansion ratio of the diffuser, effectively making the diffuser longer than its meant to be. Williams and Toyota also exploited this idea in 2009 albeit using the full width of the diffuser too.
Blowing the exhaust over the diffuser will be exploited by all teams. This will be most easily done by having low exhausts, blowing onto a gurney on the top or side of the diffuser. The rules demand two exhaust outlets, so multiple exhausts are not allowed, equally blowing into the diffuser is not supposed to be allowed. The only openings in the diffuser are the starter motor hole and a 5cm area on the outer section of floor.
Exhausts could be routed to this outer section of floor, but routing the large diameter exhausts across the floor could create their own blockage effect in-between the rear wheels. Offsetting the benefit they are supposed to provide.
However, the starter motor hole could be exploited! If the left and right exhausts were joined and then split into a upper and lower exit, one smaller exit could blow into the starter motor hole, the other exhaust would blow over the top of the beam wing, allied to a big gurney flap. This meets the two exits and no-opening rules. The exhaust routing might be a bit tortuous though.
Above all this the rear wing has no scope for active or passive f-ducts, the driver adjustable wing effectively makes those solutions redundant anyway. As rear downforce will be lost from the diffuser, the rear wing will need to recoup some of the losses. The middle 15cm of wing are still free for additional slots and wing profiles. So we can expect the usual slots and perhaps the mini winglets normally only seen a high downforce\high drag tracks.
One innovation could be to use this mount for this winglet and perhaps the rear wing support pylon as continuations of the shark fin. As the fin must not extend behind the rear wheel, equally the rear wing may not reach any further forward than before. With a rear wing fin the flow off the truncated shark fin could reattach to the RW fin. Regaining some of the yaw control and flow straightening effect of the longer 2010 style shark fins.
At the sharp end the front wing no longer needs to be quite as powerful, as it only needs to create downforce to balance that available at the rear, in doing so matching the ‘centre of pressure‘ to within 1-2% of the mandatory weight distribution.
Front wing designs have converged towards the downturned ends of the wing creating the endplate, then a remote vane being fitted to direct flow around the front wheel and also meet the FIA minimum surface area for bodywork ahead of the front wheels.
As McLaren found in 2010, the cascade can be split to encourage flow either side of the front wheel. Many team started to play with camera mountings, to place them aft of the Dwg7 neutral centre of the wing, This is likely to be a feature for many teams front wings, to create a little bit more wake-friendly downforce.
As regards flexibility, we saw obvious deflection on cars front wings last year. These met the both the original and uprated FIA deflection tests. Thus a precedent has been set that wings that are seen to flex, remain legal as long as they meet the deflection tests. Thus most teams will be looking at the composite lay up of the front wing to allow the vertical deflection test to be passed, with the wing then deflecting with the compound load (both longitudinal and vertical) seen when on track. It’s a concern that teams will have to exploit this to remain competitive. There’s a risk of wing failures, as teams find what the structural demands are for a aero-elastic wing.
co-incidentally seen on the McLaren