The Formula 1 engineers are entering completely new territory with the 2022 technical regulations. In a five-part series, we'll tell you how the complicated rule text affects the look of the cars. Part 4 is dedicated to the underbody and the diffuser.
At the end of February, the secrecy will finally be over. Then the 2022 generation of racing cars will venture out of cover for the first time in the winter tests. In our five-part series, we are already revealing to you the details in which the cars will change particularly significantly.
Episode 1: Nose & Front Wing
Episode 2: Front Axle & Wheels
Episode 3: Bargeboards & Sidepods
Episode 4: Underbody & Diffuser
Rear Wing. & Beam
Air ducts produce downforce
The most interesting area of the new cars is unfortunately hidden where you can't see it. For 38 years, F1 racers drove on a flat floor. Now, for the first time, two separate channels are drawn in from the front end of the sidepods to the rear.
In the future, these tunnels will generate the majority of the total downforce - and with significantly less air resistance than would be the case with wings on the top. In addition, the contact pressure is not so dependent on a clean flow of the car, which means that you can follow the car in front more closely.
Up to four so-called vortex generators are permitted at the entrance to the new channels just before the side box. These are small vertical fins that create artificial vortices. These accelerate the flow of air through the tunnels and intensify what is known as the Venturi effect, which sucks the car onto the asphalt.
Tunnels are flatter in the middle
This is a very sensitive area in which aerodynamicists will invest a lot of development effort. The regulations are of course particularly complicated at this point. The game options are limited. Even die-hard technology fans should find it difficult to spot differences, which is not only due to the fact that this area can hardly be seen from the outside.
The shape of the ducts in the underbody are also limited in terms of variation. But even small differences are likely to be of crucial importance for the competitiveness of the cars. It is particularly important that no air escapes from the ducts or penetrates from the outside.
At the front, the ducts protrude significantly higher into the chassis than halfway to the rear. In this central area there is a particularly great need to seal the flow highway. Therefore, small additional fins on the outside are also allowed here. At the rear of the diffuser, the air can then expand upwards again, which leads to the suction effect that increases downforce.
When is the first one hanging on the hook?
By the way, as before, the so-called "plank" between the two channels is directly above the asphalt. It used to be made out of wood. In the meantime, a composite material that resembles a wood structure is often used. As before, the plank must have a thickness of ten millimeters. Whereas the buffer between the chassis and the road used to be rectangular, the sides of the new model now converge slightly towards the front.
Unfortunately, you will rarely see the exact shape of the plank and the adjacent tunnels. At most, if a driver accidentally breaks down on the route and the car is hooked up by a recovery crane. The indentations are so deep in the underbody at the front and rear that a photographer has to crawl far under the car to get all the aerodynamic magic in the picture.
Curious looks at the underside of their vehicles are likely to be even less desirable in the future than in the past. Whoever has the air under control here can gain a decisive competitive advantage.
Diffuser in a new format
Fans and technicians also have to rethink the shape of the diffuser at the rear. The outlet of the canals will be only 75 centimeters wide in future. Previously, the horizontal edge stretched over 105 centimeters and thus almost the entire distance between the two rear wheels.
In the future, the air may only expand upwards here, but no longer outwards. In the future, the edge will protrude up to a height of 31 centimetres. For comparison: Previously it was only 17.5 centimeters. This is also intended to reduce harmful turbulence behind the car.
Because the underbody will play the main role in the production of downforce in the future and the variations are limited by the regulations, F1 technical director Pat Symonds fears that the teams will explore the limits of what is allowed here with flexible parts: "We have to, especially in the Pay attention to the area of the wing profiles under the car and the diffuser. You can get a lot of lap times there with certain tricks."
The targeted stall on the diffuser should also become an issue. This would reduce air resistance at high speeds. Mercedes made a lot of headlines with its lowerable rear at the end of 2021. The discussions about the legality of certain innovations will therefore continue in the future.