The F1 Car: Aerodynamics

Aerodynamics is one of the most important factors that engineers and designers have to take into consideration when designing F1 cars each year. Aerodynamics can mean the difference between qualifying on pole and missing out by just fractions of a second. In this first installment of the F1 Car series of my blog, I am going to be discussing everything that I can find and learn about the aerodynamics of Formula 1 cars and teach you all about it!

Now, for those who don't even know what aerodynamics actually is, here is a quick definition. Aerodynamics is the study of the properties of moving air and the interaction between the air and solid bodies moving through it. Basically, it's looking at how airflow affects how an object moves and how we can make that object go faster or move more with the air rather than against it when that object is moving.

As a car, or any object really, moves, the air it "moves through" will have an impact on how fast it can go or how it reacts. For our purposes, if a race car wants to go super fast but it can't no matter how hard the driver pushes it, it means the car has a lot of drag. Having a lot of drag means that the air you are moving through is not moving past you effectively and is essentially moving against you and slowing you down. This is exactly what F1 engineers need to avoid. They need to ensure that the air moves as smoothly through and around the car as possible, in order to get minimum drag, just the right amount of downforce and maximum speed output.

Key notes: The difference between drag and downforce

Drag - comes from the front of the car; basically the air you're driving into resists your forward motion, which slows the car down

Downforce - air pushes car down to increase grip; air creates force to keep the car down

There is, however, a balance that these engineers need to find between airflow, weight and the forces (downforce and drag) these two factors create. Downforce is the most important factor that aero-engineers need to focus on. They need to ensure that air can flow through the car to ensure that the car will be fast enough on straight portions of the track, but also have enough downforce to get through the corners at top speed and ensure that the car stays on the track and doesn't go flying into the grandstands. If a car goes very fast without enough downforce, air can get underneath and lift it off the ground. The car they design must also be light enough to reduce drag and maintain top speed, but still heavy enough to stay stable and avoid lifting off at high speeds.

There is a catch: this carefully crafted balance is disrupted pretty easily. Anything from damage to the car to weather conditions to altitude can affect how well the car can produce downforce. A collision on track can result in a simple fix during a pitstop or retiring completely from a session or race. Windy conditions on track can mean losing control of the car due to a tailwind (wind coming from behind) or being able to take a corner faster thanks to a headwind (wind coming from the front) creating more grip. A higher altitude means that the air is thinner and therefore less air particles, which results in less downforce due to less air particles being available to push the car down. Every weekend brings different challenges for the aerodynamic engineers!

Here's a visual of all the forces that act on an F1 car.

Photo Credit: @myroslavsyupka on medium.com

There are 3 key areas where aerodynamic engineers focus their energy on: the floor, the wings and the shape of the car.

1 - The Floor

The floor is the biggest contributor to the aerodynamics. Pretty weird, I know. So far, you've probably been thinking that "the wings are the most important" or "the shape of the car is more important", but you would be mostly wrong. The floor of these cars is arguably the most important part as it generates a large chunk of the downforce an F1 car needs. It is also the most heavily regulated and inspected part of the car (more on the FIA and its regulatory practices in a future article!).

Let me explain:

The floor of an F1 car is designed and shaped to manipulate air as it flows underneath it, which creates areas of low pressure under the car. This creates the all important downforce. But how is it designed and shaped? A combination of the ground effect and Bernoulli's principle is used. The ground effect is an aerodynamic phenomenon where the underbody of the car is shaped into Venturi tunnels (sculpted channels under the car's floor) that speed up airflow and creates a low-pressure area, which sucks the car to the track and generates high downforce with minimal drag. Bernoulli's principle is a principle in fluid dynamics that states that as the speed of a fluid (which is a liquid or gas) increases, its pressure decreases.

Here's a visual for you.

Photo Credit: autoracer.it

The air comes in through the front of the car and comes out the backside of it through the diffuser, which yet again, accelerates the air.

The key takeaway from all of this physics talk is this: the main job of the floor is use air pressure and air acceleration to create downforce.

In 2022, the new car regulations came out and there was a focus on the floor, the diffuser and how they were designed. These new regulations were put in place to help reduce how turbulent the air flow on the back end of the car is. This turbulent air flow, known as a wake, made it very difficult for the cars to follow each other, resulting in a lot of racing issues. These new regulations led to a lot of headaches for the aerodynamic engineers as they had to completely redesign the floor of their cars. One of these issues was porpoising. This funky word describes when the body of the F1 cars would bounce up and down while they were driving. This happened when the floor sucked the car down so much that airflow under the car stalled, causing a sudden loss of downforce. The car would then bounce up again, regain airflow, then get sucked down again, creating a headache-inducing, never-ending cycle that irritated both the engineers and the poor drivers who were constantly bouncing up and down. This became a common issue amongst all the teams thanks to these new regulations that forced cars to run at very low ride heights (the distance between the bottom of the car and the track).

Photo Credit: Reddit

Here's a little fun fact about the floor of an F1 car: there is a part of it that is a plank made of wood! Yes, these mechanical beasts have a long plank of wood that runs along the bottom. Weird, I know. The plank used to be a lot longer but the new 2022 regulations made the plank shorter due to the new focus on the floor. Here's what it looks like.

2 - The Wings

The next area that affects aerodynamics is the wings. There are 2 different wings: the front wings and the rear wings. Both sets of wings are very important when it comes to directing airflow into the car and creating more downforce. The wings are designed to make the air flow over them, which generates downforce. The end plates of the wings are designed to control vortices (swirling masses of air) and reduce drag by guiding air flow, which makes the car go faster.

Key Notes: Dirty air = turbulent airflow that comes off the back the car in front of another car

→ makes car behind have less downforce = less grip = can't maintain speed & struggle to overtake when on corners

→ on the straights, being behind another car is a good thing because of the slipstream = being behind a car will shield the other car from oncoming air, which results in less drag and being able to go faster

The front wings are very sensitive because it is the first part of the car the air hits. Any little bump or collision can change how air flows around the whole car, which offsets the balance of the front wing, which in turn messes with the balance of the whole car, grip and tire temperatures. They did become less sensitive with the new 2022 regulations, which made the front wings simpler and have less parts, but they are still easily susceptible to damage. The endplates are normally the first to go when the cars collide. But besides being sensitive, the front wing's main job is to control the airflow around the car and provide stability during high speeds and corners. Being the first part of the car that interacts with the air, the front wing is super important for the performance of the car as a whole. The front wing will direct air under the car towards the floor so that the floor can do its magic. It influences everything from the car's grip when going around corners to the effectiveness of all the other aerodynamic surfaces of the car.

The rear wings create a big chunk of the non-floor downforce. It does this by acting as an upside-down airplane wing. Weird comparison, I know, but think of it like this: an airplanes wings are used to make it lift off the ground and into the air, while an F1 car's rear wing does the opposite. It forces air to travel faster over its curved top surface and slower underneath. This difference in speed creates a pressure differential, with lower pressure on top and higher pressure below. And because pressure is lower where air moves faster (Bernoulli’s principle again!), this sucks the car downward. The difference in pressure pushes the wing (and the car, obviously) down onto the track. This negative lift, or downforce (our term of the day!), provides crucial grip for going around corners at high speeds. 

The rear wing is also used during DRS — Drag Reduction System. I talked about DRS in my F1 101 article, but for a quick recap, DRS is when the rear wing of the car opens, allowing for more air to flow through the car, which lessens drag and makes the car go faster. This system gives the car a temporary straight-line speed boost, making overtaking much easier. However, it can only be activated when a car is 1 second or less behind the car in front of it.

3 - The Body

Photo Credit: carmagazine.co.uk

Finally, the shape of the car plays a key role in how the air moves through and around the car. The modern F1 cars are kinda shaped like a soda bottle. Here's picture of the 2022 regulation car that the FIA released. But why this very wide shape? Well the big things on the side of these cars are called side pods and their job is to manage airflow for aerodynamic performance and the all important cooling. All the radiators and cooling systems for the car are in the sidepods, which makes sense because while the cars are moving, air will flow into these sidepods, bringing in cool air and cooling down all the systems within the car that are being pushed to their limits. Of course, they also have aerodynamic purpose too. The shape of these body as a whole and the sidepods are designed to control and direct airflow over and around the car to reduce drag. They also direct airflow towards the diffuser and the floor to, once again, create downforce. The sidepods and the body of the car are able to do all of these cool things thanks to the inlets that help direct the air to where it needs to go

This big part on the side of the car is the sidepod and all the holes along the side and in front of the sidepod are the inlets.

Photo Credit: the-race.com

Fun fact!

The teams use a huge wind tunnel to test and design the aerodynamics of the car. The amount of time they get to use this wind tunnel will depend on where they end up in the Constructor's Championship. The higher up a team is in the championship, the less time they get to use the wind tunnel to test the aerodynamics of their car.

The moral of this long spiel about all the aerodynamic parts of the F1 cars is this: downforce is everything when it comes to aerodynamics and pretty much the whole car is designed to generate, manage and balance downforce.

I hope you enjoyed the first installment of my F1 car series, which is where I breakdown the main areas and systems of the car. Please let me know if I missed any spelling errors.

Until next time my lovely readers!