The Mercedes F1 brought an upgrade package to the W13 in the 2022 F1 Bahrain test with a slim side pod called the “Zero Pod”.
The extreme design has created a side pod that looks almost non-existent when compared to rival teams. All that remains is a small bump in the chassis with a long vertical slit as the air intake for the internal cooling system.
The boldness and structure of this design has sparked some tweets that it may not follow the “spirit” of regulation. But what purpose did this sidepod serve and how did Mercedes achieve this engineering feat?
In F1 aerodynamics, controlling the wake of the front tires has always been an important differentiator for performance. The air turbulent by the front tires creates a very volatile “dirty” flow that, if left uncontrolled, impairs the aerodynamics of the rear of the vehicle.
The wide side pod design by Ferrari, Haas, Aston Martin and others controls the fake of this front tire by physically “pushing” the wake of the tire in the same way that the bargeboard was responsible for. It is an object.
Mercedes F1 took a completely opposite approach to controlling the fake of the front tires with this very narrow side pod.
“There are two ways to do it, one with wide side pods and the other with narrow side pods, and we obviously took that route,” Mercedes F1 technical director Mike Elliott told Sky Sports.
“Of course, it’s visually very different, but it’s only a slight difference in what we’re trying to do aerodynamically.”
“We use a narrow side pod layout to prevent the tire wake from sticking to and pulling in the side pods, but other teams have adopted a route that pushes the side pods as far as possible to push it out. There are only two ways to do the same thing. “
Mike Elliott’s comments provide insight into the aerodynamic concept behind the side pod design. Mercedes was able to tightly package the cooling design into the chassis, allowing it to use aerodynamic devices to control the wake of the front tires instead of using the side pods themselves.
The “turning vane” above the new side pod design with mirrors houses the upper impact structure. This structure is angled so that its surface creates a downwash to provide a high pressure area underneath. To complement this, the side pods are also flared outwards to create another high pressure area, the outwash.
These high pressure areas serve behind the front tires and in front of where the “coke bottle” section of the chassis begins. The front tire wake is “pushed out” by this high pressure area, effectively doing the same thing as a wide side pod.
The Mercedes F1 has introduced a larger cooling louver on the new engine cover, above the new side pods, to expel hot air from the cooling system. The first few runs in Bahrain were taped and the cooling louvers increased from two in Barcelona to a total of five. This is probably due to the hotter climate in Bahrain.
Nonetheless, these outlets provide a slow air flow that is guided over the diffuser towards the rear of the car, helping to create a high pressure area that increases downforce generation.
The Mercedes F1 has also updated the floor design because the side pods are much narrower. Especially upstream of the side pods, the outer turning vanes are significantly larger, similar to Red Bull Racing (1). It acts like an old-fashioned barge board and helps push the bottom of the tire wake out under the floor and through the entrance to the side pod area.
The design of the front wing has also been updated, changing the flow of air downstream. The top element of the front wing is small and the end plate is twisted to push air around the tire and minimize wake from tall 720mm tires.
A mental problem for many in the paddock is the legality of the new side pod design. The focus is on Section 3.7.1 of the 2022 F1 Technical Regulations. This section defines what the bodywork declared as a “side pod” must comply with.
This section specifies that the side pods “when intersecting the X or Y plane, they must form no more than two curves on their outer surface, each of which must be tangentially open.” ..
Also, “In the X plane, the curve seen from the side of the car must not contain a concave radius of curvature of less than 200 mm.” “In any Y plane, two curves are visible when viewed from the front of the car. In all cases, neither curve can have a concave radius of curvature of less than 200 mm. “
The Mercedes F1 side pods appear to be compliant, as all curvatures in the design appear to meet the specified radius.
The more difficult part to define legality is the shrouding of the side impact structure. The FIA’s technical regulations on side impact structures focus primarily on safety and proper mounting of the structure on the chassis and assume that it will be contained within the side pods, so the shroud around the side impact structure The shape is not restricted.
Section 13.5.1 only states that “the two side impact structures must be completely surrounded by the vehicle body, so some of them must not be exposed to external airflow.”
Given that the Mercedes F1 has already provided CAD models and drawings to the FIA, this shape also seems to be regulatory compliant. Even Mercedes F1’s rival Red Bull Racing admits that the design looks legal.
This radical new concept that Mercedes F1 chose in its side pod design all stems from its ability to package the cooling radiator very tightly into the chassis. The Mercedes F1 may have designed the chassis with this in mind, so it will be difficult for other teams to duplicate it.
The radiator is pushed into a monocoque near where the fuel cell and ERS battery pack are located. Since the flow velocity is relatively slow near the surface of the radiator, the radiator can be retracted into the monocoque and flow directly there.
To reproduce this, the F1 team will need to completely redesign the monocoque, or at least redesign this section of the monocoque to rehomologate the survival cell. It is unlikely that any F1 team will be able to achieve this within the season.
Pat Symonds, F11’s technical director, gave insight into how Mercedes F1 did this.
“This is a very novel approach,” Pat Symonds said in an interview with Sky Sports.
“We have developed this series of regulatory aerodynamics. We have considered not only the generation of downforce, but of course, braking cooling, tire heating, especially engine cooling, and much more. For cooling. , We were using a larger inlet than the W13. “
“For Mercedes, there are some small tricks that can help in this regard. For example, the intercooler is a very clean device. It’s a little different, although Mercedes has been using water / air intercoolers for some time. I think”
“I think the intercooler comes from people using Oxfordshire’s Reaction Engines air breathing rocket motors. Something like a spin-off from there is a very efficient heat exchanger technology.”
“And I think that’s part of the reason they were able to produce cars the way they adopted.”
Category: Category: F1 / Mercedes / F1 machine