F1 for Speed

There’s more to F1 cars than powerful engines. Aerodynamics, gravity and smart design work
wonders on the track.

The modern formula one (F1) race car has a lot in common with an advanced jet fighter. A majority of these common features come from the aerodynamic considerations that go into its design.

To truly understand aerodynamics in F1 cars, we’ll have to look at the various forces, aerodynamic and otherwise that act on an F1 race car (or for that matter, any moving body in the atmosphere). One of the largest forces that act on an F1 race car is its thrust - the driving force supplied by the engines, through the wheels, that causes it to move forward (acceleration). In an F1 race car, this force is often several fold greater than regular cars, although the total weight is much lower than a road car.

The second force, known as drag, acts in the opposite direction to its motion (backward) and is due to air resistance. A core function of aerodynamics in F1 race cars is to minimize this drag force. The weight of the car, caused by gravity is the third force and acts in a downward direction, to keep the car to the ground. A fourth, very important force, is the aerodynamically created downward force, which acts more or less in the same direction as the weight of the car, to keep it pressed downward. In modern F1 cars, the down force can reach magnitudes as high as 3.5 times the weight of the car.

While the driver can vary thrust by changing gears and revving the engine, the weight is constant. The drag and downward force are largely a function of the speed of the car (and hence not directly under the driver’s control).

Function of aerodynamics

In the 1960s, with stagnation in internal combustion engine technologies (all path breaking developments had already been made, with further developments leading to only minor refinements), new ways had to be explored to improve the performance of a race car.

One of the first steps in this direction was the realization that the weights of the cars could be further dropped (allowing them to become lighter and hence faster), while the function that weight served, of keeping the car pressed to the road during curves and slopes, could be passed on to aerodynamic forces. The result of this line of thought was to fi t wings onto F1 race cars. Though similar in many ways to aircraft wings (in their cross sectional geometries), the wings in F1 race cars are mounted upside down, (in a manner of speaking) to create down force rather than lift (the upward force that helps an aircraft fly).

Alongside, the overall geometries of an aircraft were also altered to reduce drag, so that the total force causing it to accelerate could be increased. The result was rapid and explosive development in these sectors often leading to catastrophic disasters, causing the racing regulatory authorities to follow up with strict regulations, in the interest of safety. The 1970 racing season witnessed a new set of regulations, on the size and location of wings in an F1 race car. Ever since, the aerodynamics have played a large, often pivotal role in F1 race car design, characterized by regulations for safety considerations, quickly followed up by clever innovations by designers. Today, the more popular F1 race cars spend upwards of $100 million on aerodynamic design, with up to $50 million spent on construction of wind tunnels, much in the same way as the design of modern aircraft.

Today, the core function of aerodynamic considerations in the design of F1 race cars is to:

• Reduce drag, so that the forward acting force and acceleration can be maximized.
• Increase down force, so that the car is highly stable and can take tight corners by hugging the ground.

Let us take a look at how it is implemented. The different aerodynamic components of an F1 race car are as follows:

Wings

The wings of an F1 race car are located near the nose and toward the rear are the most important aerodynamic components of the car. Their function is to provide a downward force that causes the car to hug the ground. The front and the rear wing together provide more than 50 per cent of the down force between them and hence play a crucial role in stabilizing the car. In many cars, these wings are movable by the driver, to a large extent, so that he has control over what component of the down force is provided by each one individually.

The Diffuser

A component found towards the rear bottom of the car, it is curved slightly upward and functions to reduce the turbulence in the airflow below the car. The final effect is that the airflow below the car, being less turbulent than the one above, is now at a higher speed, and hence lower pressure (Bernoulli’s principle by which aircraft wings create lift). This causes the car to hug the track (due to more downward force).

Airflow over a Renault formula 1 race car, generated using the software Fluent 6

End Plates

The end plates, found perpendicular to the front wings at both sides guide the air smoothly along the sides of the car, so that turbulence and drag is minimized.

The Bargeboards

Although these have been done away with since 2009, the function of bargeboards when they existed earlier used to guide the air sailing past the front wheels into the engine radiator intakes for engine cooling.

While the above mentioned are the most important individual aerodynamic components, many smaller ones such as flip ups, turning vanes and nose cone holes exist over the geometry of the car as per individual requirements. While flip ups are controllable components used to increase down force, a turning vane produces extra turning force by redirecting airflow. Nose cone holes serve to reduce shock and hence drag.

Flip ups on a Williams Formula 1 race car

Turning Vanes

Apart from specific aerodynamic components, almost every part of an F1 race car is designed with aerodynamic considerations. The whole body is designed to act like an air foil, providing further down force. Engine intakes and exhausts are designed to avoid turbulence. Even the wheel surfaces are designed to avoid turbulence.

Formula 1 race car aerodynamics has been a constant race of one-upmanship between the regulators, with safety concerns in mind and the designers who immediately come up with clever innovations to avoid reduction in aerodynamic performance. With neither side likely to give up anytime soon, we can expect a lot in the way of development in F1 race car aerodynamics in the future.