Mercedes AMG F1 W05 front wing analysis

The W05 featured from its launch a surprising amount of detailing all around the car, with at its head a very elaborate front wing. Much too detailed to be just a wing for early-days testing, they left it unchanged for all pre-season winter tests. I believe this wing will not change a lot, most likely some small tweaks, between now and the first race in Melbourne, being a very critical part for the airflow structures all around the car. This allows for an in-depth analysis, which I broke down to 4 parts: the endplates, cascades, basic wing and the complete picture.

Endplates

In the months before any 2014 car was launched, it became clear teams would have a challenge with getting air around the wheel, avoiding drag and turbulent airflow coming from the wheel wake, because of a reduction of 75mm on both sides of the front wing. Many, including myself, believed teams would choose to sacrifice even more front wing area to create endplates that bended more aggressively to get air away from the wheel.

Surprisingly, most teams chose not to. This is because they converged, throughout the years, to an “endplate-less” design. They for fill the mandatory bodywork that makes up the endplate, but actually let the front wing itself do most of the work in getting air around the tire. Still, since the endplate has to be there, teams utilize it to help the front wing in this aspect.
Mercedes’ solution actually goes way back to its 2009 predecessor Brawn team. Just getting started with radical aero rules changes, they came up with a unique solution of 2 smaller endplates partly overlapping each other. That year included, Mercedes actually kept that very same design for 3 years, with only very subtle changes. Such was the efficiency of its design. Coming into 2012, they made changes to it, resembling more closely its current iteration:

Being remarkably simple, it does have a few functions. Air coming from the lower wing elements gets leaked out in the gap in between the 2 endplates. The latter endplate meets up with the last 3 front wing elements, bleeding off more high pressure at that point. The endplates bend subtly outwards, just enough to direct air away from the wheel. Interestingly, Mercedes copied a solution from Lotus F1, adding a small flap to the latter endplate:

Lotus came up with this solution, albeit in a slightly different form, at Spain 2013. Its purpose isn’t completely clear, but I believe it tries to keep the faster moving air coming from the outer edges of the first wing elements, close to the footplate, not interrupting with the slower moving air coming from the latter wing elements, which have a higher angle of attack. That way the higher pressure air doesn’t get sucked in the lower pressure air and avoids contact with the wheel wake. A vortex will probably also be created at its tip, further separating the 2 flows. It’ll probably create a little bit of lift and drag, but it should overall have a beneficial effect.

Plain Wing

The front wing itself is also a clear evolution from last year. They kept the same amount of elements, 5, but while only the upper element had a slot through and through, this year the 2 upper elements are just that.

More elements and longer slots keep the wing from stalling at high angles of attack. While technically they can use that for higher angles of attack, I believe it’s more a solution to the turbulent air from the rotating wheel, which normally messes up the airflow beneath the wing. Bleeding off cleaner airflow to underneath the wing will help in keeping airflow underneath the wing attached, preventing sudden downforce loss.
The endplate-less design becomes very apparent with the other parts removed. The outer edges of the elements try to roll up the airflow into a powerful vortex, accelerating air into an outwards bending flow. The upper element has its highest AoA nearer the edges, with a very interesting setup around it.

First of all Mercedes added a small inverted gurney flap right on top of the element (highlighted in light blue) and also right in front of the tire. Air underneath it gets blocked, creating a rotating flow structure. This will push the rest of the air much higher, again to ensure minimal interference from the tire. They aid this process with what must be the most twisted carbon fiber piece on the grid (yellow). This piece spans over the 2 uppermost elements and together with the endplate boxes in airflow in the path of the tire, separating it completely from the other airflow. While this solution isn’t beneficial for downforce creation, it does help significantly in reducing wheel drag, and also creates a low pressure field behind it, sucking in air coming from underneath the front wing. Also note that the twisted vane is integrated in the wing flap adjuster, which curls back down to the middle element. Clearly a lot of effort has been put into this.

The 2 elements that have slots through and through create a vortex at their tips. Last year Mercedes only choose to do so at the uppermost element, but this year they saw it needed to have 2 tips creating a single stronger vortex. This vortex passes along the Y250 line, a critical area for airflow moving to the splitter and floor.

Cascades

This part has been largely overhauled since last year, yet also keeping some trademark solutions. First of all, Mercedes dropped the r-winglet, which created a bit of downforce. Since downforce levels have been reduced, that winglet is less needed. The R-winglet also created another vortex along the Y250-line, but Mercedes felt a stronger vortex at the wing tips could do the job as well. We’ll see if the r-winglet pops back up during the season.

Mercedes expanded the cascade attached to the endplate, added a J-part (yellow), added a small vertical turning vane (blue) and twisted all vertical pieces outwards, in an aggressive attempt to get again air away from the tires. Also note they kept the small flick at the middle plate of the cascade (red circle) (this was the inner endplate of the cascade in 2013), as well as the IR sensor (green).

Complete Picture

The parts I’ve spoken about of course don’t work on their own, but act in conjunction to each other. The mounting pillar of the cascades for instance is placed right in the path of the flap adjuster piece, directing air from the second it touches the wing. Vortices coming off the vanes and plates of the cascade set up airflow structures that close off even more the ‘boxed-in’ airflow ahead of the tire. The Y250 vortex will also meet up with the turning vanes underneath the chassis further down the road. And air between the endplates and wing elements gets nicely guided towards the last element which bends the airflow very aggressively away from -yet again- the tire.

It also shows that modern front wings are just way more than downforce-production devices, acting as complex flow conditioners to both set up airflow patterns across the car and minimizing wheel drag.

All in all this a very detailed front wing to start the year with. I don’t see any major overhauls coming just yet. However, with the team bound to recuperate more and more rear downforce across the season, they will have to gain the same amount out of the front wing. Changing the angle of attack isn’t as convenient as in the past, influencing airflow, forcing perhaps at one point to completely overhaul the front wing. However, for now they clearly have a strong base to build on.