Technically, 2021 is meant simply to be a holding season earlier than the pandemic-delayed, all-new formula of 2022. However two apparently small tweaks to the tyres and aerodynamics of the present vehicles for subsequent 12 months are introducing a possible volatility into the aggressive order, as Mark Hughes explains, with technical illustrations from Giorgio Piola.
The modifications of a brand new tyre development – which shall be trialled throughout Friday follow in Bahrain this weekend – and the clipping of the floor and associated aero changes are quite small, however their results could also be a lot larger.
Groups should retain their present tubs into subsequent 12 months, however the bodywork can nonetheless be developed round that. Nevertheless it should embrace the narrower ground with none of the bottom impact sealing slots in addition to a brand new limitation upon diffuser strakes and rear brake ducts. This has been legislated to counter the anticipated will increase in downforce from staff improvement on this unanticipated closing 12 months of the present method.
Merely becoming the unslotted narrower ground and trimming the aero gadgets as required to a present automobile would make it authorized – however the impact on its competitiveness could be disastrous if there have been no accompanying modifications made.
Mercedes technical director James Allison provides an thought of the size of change, explaining, “The change in its uncooked, un-optimised kind, simply chopping the issues off the automobile… and our automobile would go from pole to comfortably final.”
The groups are having to discover a new approach to optimise the realigned airflow – and that could be a main job in itself. However issue into that, the modifications in tyre which might have an enormous impact on the automobile aerodynamics. It is for that reason that Pirelli provides the groups with wind tunnel tyres that replicate the true factor. A brand new tyre development will imply new wind tunnel tyres – and the groups haven’t but seen these.
Balancing the aerodynamic load between the entrance and rear axles is a serious endeavour of all of the groups. It’s diversified from circuit-to-circuit as required, however is successfully restricted to inside a spread by the automobile’s design. Getting that stability proper in all of the completely different variations of trip peak, yaw, pitch and steering angles the automobile sees is essential to getting and retaining the tyres of their right working window.
Harder development tyres will usually be harder to deliver into the temperature window, because the core shall be extra proof against the bending forces that generate warmth within the rubber. The groups manipulate the airflow by the brake ducts and into the wheelrim to switch warmth from the brakes into the tyre (or take it away in hotter circumstances).
A modified requirement of how a lot warmth to switch to the tyres is a serious undertaking – and the requirement can’t be absolutely recognized till the groups have finished some working on them. Hence the Bahrain running on the new spec this weekend shall be crucially necessary.
There was a ‘blind take a look at’ of the brand new spec in Portimao however the compounds have been diversified and the groups weren’t instructed which compounds they’d. That take a look at was extra for Pirelli’s understanding than that of the groups.
This time, the brand new tyre shall be with the C3 compound, so giving groups a direct comparability to the current-spec C3 that shall be used for the remainder of the weekend. Groups shall be supplied with two units, one among which have to be utilized in FP2. The opposite set can be utilized in any follow session. On the Abu Dhabi Grand Prix, the softer C4 model of the brand new tyre shall be examined throughout Friday.
A stiffer development of tyre will are inclined to deform much less underneath cornering load – and on the rear this has an unlimited impact on the airflow across the diffuser and therefore how the entire underfloor works. Optimising these flows in an especially aerodynamically delicate a part of the automobile is a vastly complicated job – and with the limitation of the diffuser vane size and brake duct vanes, the groups have fewer instruments with which to govern that move.
The tyre, the suspension and the aerodynamics work collectively to get the tyre into the required window – and the impact of not getting it proper might be catastrophic. It’s why, for instance, the Mercedes was recently 5s off the qualifying pace at Istanbul. So altering two of these elementary variables just isn’t a trivial matter.
“The aerodynamic change is fairly huge,” says Allison, “and will simply change numerous the traits that we have taken without any consideration for the final two seasons.
“So it is fairly an anxious time in the intervening time, ensuring that we recuperate as a lot downforce as we will from the regulatory wounds that have been inflicted on the automobile simply these days, and to scramble as a lot data out of the following two races as we will on these two tyre checks that we are going to get to do with the brand new rubber. After which hopefully have the ability to glue all these items of data again collectively in time for winter testing subsequent 12 months.”
It’s removed from a on condition that these modifications will influence equally on all of the vehicles. The truth is historical past tells us they most likely received’t…