How Mercedes made the curve with its razor-sharp W12

It had to face the reality that new regulations hindered low-rake runners more than their high-rake counterparts.

However, while Aston Martin, another low-rake runner, continued to struggle to maximize its package in response, Mercedes has made significant strides with its car.

Because although Lewis Hamilton’s W12 was still a bit called a “knife edge”, the car has become noticeably more stable over time – and that has brought it closer to Red Bull.

The team’s focus on development and setup was clearly on the rear of the car, with the team evaluating two rear wing options during free practice in Imola on Friday.

Both had slightly different levels of downforce, but perhaps more importantly, they had different buttress designs.

This is not a new tactic for Mercedes as Mercedes has spent a good part of last season running similar tests to understand which tradeoff fits their qualifying and race requirements, affecting DRS one of the factors.

Another area where the team tried to improve their stability issues was in a revamped strake design for their diffuser.

The layout of the strakes was largely carried over from last year’s design, albeit with the lower 50mm cut off to comply with the new regulations.

For Imola, however, the secondary line of strakes has been changed, swapping the L-shaped design used in Bahrain for a full-length version (highlighted in green, below).

Mercedes W12 diffuser comparison

Photo by: Giorgio Piola

Meanwhile, it appears that the surface coating of the diffuser transition has also been modified for the second race of the season, possibly to maintain flow and stabilize the performance of the middle section of the diffuser.

Mercedes AMG F1 W12 diffuser comparison

Photo by: Giorgio Piola

Red Bull 2021 rhinoplasty

Red Bull spent a significant amount of its time battling a correlation problem early last season when the company discovered that its real-world performance was inconsistent with the information provided by its simulation tools.

One of the most important changes the team went through during this phase was a change in the nose design philosophy, with the team switching to the almost universally used Cape solution.

During this time, the team alternated between a narrow and wide pillar mounting position, but the rest of the assembly remained relatively unchanged.

Red Bull Racing RB16B front wing

Photo by: Giorgio Piola

After issuing its engineering stamps on the rear of the RB16B, one might think the nose saw no action, but a sizable chunk of the body was placed on the cape behind the nose box.

Once placed on the car, that section of the cape slides in to hit the chassis, with the new body filling in part of the void you previously found filled by the airflow.

Red Bull Racing RB16B front nose comparison

Photo by: Giorgio Piola

Z-shaped bottoms

A regulatory change always seems to offer us different technical solutions to the same problems, and this this year in the form of two different floor cutout concepts.

On one side of the fence falls a group of teams that have followed the intentions of the regulations and use a fully tapered bottom edge, while on the other side we have a group that uses a Z-shaped cutout.

After testing, there was a 60/40 split in favor of those who used the fully conical solution. However, as early as the second race of the season, this split turned 70/30 in favor of the Z-shaped solution, with Alpine taking it over in Bahrain and Ferrari and Williams arriving at Imola with their own version.

Ferrari SF21 floor

Photo by: Giorgio Piola

Ferrari’s takeover of the Z-shaped cutout meant that the team gave up on the trio of winglets halfway along the cutout, at least for a short time. However, to coincide with the Z-shaped floor section, a large strake was added upstream (arrow).

This combined strake arrangement is used by all teams, although some have broken the strake into shorter sections (more like fins) as it appears to affect the direction of airflow over the top surface of the floor, pushing it outward and in the way the airflow generated by the cutout.

The result of the Z-shaped cutout is that part of the floor is returned parallel to the center line of the car, giving the aerodynamicists a behavior similar to the previous set of rules, albeit inward, where it would have been.

Of course, this loses some of the total available area, but if that floor area misses airflow and pressure distribution, it is useless anyway.

The accumulation of fins and strakes that find their way onto the floor section next to the sidepod (like the ones added by Alpha Tauri this weekend, below) help mitigate the loss of slots and fully closed holes in this region previously, but banned for 2021.

AlphaTauri AT02 bottom detail

Photo by: Giorgio Piola

Interestingly, while Ferrari dropped its trio of winglets in the middle of the floor when introducing its new design, the other team, which switched to a Z-shaped floor cutout at the second race of the season, didn’t.

This shows how different each interpretation of the Z-shaped cutout is, as their length is very different, meaning that the cone in front of the rear wheel is also a different length.

Williams, with its longer, tapered section at the far end of the floor, still needs that trio of outwardly angled winglets to achieve the desired aerodynamic effect.

In the meantime, at the point where the clipping is formed, the team has adopted the strake method, although Williams chose to break his up into three smaller fin-like sections.

Williams FW43B floor detail

Photo by: Giorgio Piola

Of course, there are still subdivisions in the way each of these teams deal with the Z-shaped cutout and the various aerodynamic tools that line the edge of the floor as we can see in the image below, with the yellow line being the differences each team’s approach is highlighted.

You will find that some teams have a longer section that tapers towards the front of the floor, some have a larger cutout in the middle, and some have a longer section that tapers towards the back of the floor.

Overall, the Z-shaped cutout appears to have prevailed, with the three remaining teams likely working on their own interpretation for the upcoming races to further improve their level of performance.