Tech Analysis: Lotus E22 image
Another surprise image release came from Lotus. After much speculation, we were finally enlightened as to what they were getting up to with their nose design as well as a few other interesting features.
The nose is by far the most interesting part of the new E22. Although the “finger” solution will be the most common design this year, there is a way of dodging the bullet of having the small extension at the front as an obstruction to the underside of the car. It would seem that Lotus have exploited this loophole perfectly.
The FIA require that the nose must form one single cross section – the placement of this cross section is not specified therefore it can be off centre. This is where Lotus have come up trumps compared to the other solutions seen so far.
Whereas the others have gone for a single cross section entirely, the E22’s nose has two cross sections that form a large opening in between them, allowing airflow to fill the space beneath the chassis to improve rear downforce. This is why the nose height has been steadily increasing over the past four years, as teams looked to fill the underside of the car with a higher volume of airflow.
I previously mentioned on this website that one side was a vanity panel structure and the other the crash structure itself. However, I got the wrong end of the stick as I was thinking of another potential solution that has arisen between my colleagues.
The Lotus design has two complete crash structures: each prong is made up of a carbon-aluminium honeycomb composite that can withstand the forces applied to it during the FIA crash tests.
In the regulations, the FIA mandate a single, 9000mm2 cross sectional area, complete with a 50mm length tip that must be centred around 185mm above the reference plane. These two numerical values state the requirements for the nose structure.
Lotus have successfully skirted around this regulation by creating an off-centred “tusk” that meets the regulations on the right side, with a shorter tusk added on the left. As the left tusk is shorter, possibly by around 50mm (the length of the tip), it is not deemed to be part of the regulation that outlines the nose requirements – it is merely an extension.
This design is very difficult to manufacture and I am sure the aerodynamic design team pushed for this more than anyone. Passing the crash tests must have been extremely difficult as the asymmetric format means that the load spreads unevenly up the nose as it crumples, with maximum absorption of the impact energy only met once it reaches the main body of the nose.
I would imagine that the entire assembly is a lot heavier than the average 2014 nose to pass the crash tests, so it would not be a surprise if they had other ideas to try out should this fail.
Other than the nose, the front wing appears to be of the same specification as last year for now.
A single camera pod has been placed ahead of the upper wishbone arm on the right side of the nose. This may be to do with the fact that the right side of the nose is longer and is therefore more beneficial to place it as an aerodynamic device in this region.
What is interesting about the E22 is that, despite the fact that they will be running the Renault power unit next season, both McLaren and Lotus have come up with a very similar approach to the sidepod layout, although Lotus’s solution is a bit neater.
The ‘pods themselves are bigger than last year due to the additional cooling requirements, but the bird’s eye image gives you some perspective of just how much wider they are. Before, the bodywork was far within the line of the edge of the floor, but now the sidepods bulge outwards over it.
The inlets on the E22 are actually relatively small in comparison to both the MP4-29 and the FW36, although they feed a much larger area inside as the airflow that enters it expands outwards, which in turn draws more air in.
The bodywork then tapers towards the centre of the car very quickly before forming two, straight ducts that exit as one giant exhaust by the rear wing, much in the same way as the MP4-29. This solution could prove popular because it frees up a lot of area around the centre of the car ahead of the floor. This allows for airflow to pass over the sidepods and onto the floor/top of the diffuser a lot sooner, which could prove highly beneficial.
Above the air intakes lie two horizontal blades, almost of the exact specification that we saw debut last year on the E21. These blades act in a similar way to vortex generators in that they produce downwash over the top of the sidepod and push airflow towards the floor, breaking up the boundary layer built up over the ‘pod during the process.
What is remarkable is the lack of cooling outlets other than the central ducts at the rear of the car. The other cars we have seen have all been Mercedes powered and feature a lot of louvres, gills and outlets littered all over the bodywork. This could indicate that the Renault power unit is a much more heat efficient unit than the Mercedes, as reports have suggested over the past few months.
Rear wing & Exhaust
The image Lotus revealed today helps us identify the changes to the rear wing ahead of 2014. The angle the image is at gives us some indication of how much shallower its profile is. In comparison to last year, the bottom of the main plane must finish 20mm higher. That may not seem much, but it will make a substantial difference to the amount of downforce generated by the wing and also from the diffuser below.
It is interesting to note that there appears to be no DRS actuator, although it could be housed within the endplates themselves. On the topic of endplates, Lotus have further developed this area of the car by addding further upward strakes. These strakes interact with the general motion of the airflow surrounding the rear tyres, particularly of that coming off of the brake duct scoops and flick-ups.
The exhaust exit is not visible as it is covered by the trailing bodywork that makes of the sidepod. We can tell that it is there, though, because the bodywork sweeps upwards slightly at the same angle (5 degrees) as the exhaust, as it has to this season. The position of the exit pipe appears to be as far back as the regulations allow and, for now at least, Lotus do not appear to be exploiting the exhaust gases for an aerodynamic benefit.
This is further confirmed by the lack of a Monkey Seat winglet and the use of a central rear wing pylon for support. As it is just an image however it would be easy to jump to conclusions too quickly.
Images courtesy of Lotus F1 Team
William Tyson - a Mechanical Engineering student at Swansea University - has been writing about the technical side of Formula 1 since February 2013. After joining the Richland F1 team for 2014 he has continued to establish himself as a more rounded technical analyst whilst maintaining a healthy following on his blog.