Understanding Aerodynamics in Formula E

Learn about the efficient design of Formula E’s Gen2 car… 

The movement of air has captured minds and the study of angles has played a crucial role in the refinement of speed in the world of motorsport.

Harnessing raw mathematics and physics, aerodynamics have re-defined aesthetics and it’s this pursuit of downforce that is present in almost every racing paddock.

To understand the art of controlling air, and ultimately, understand downforce, it’s important to remember Newton’s Third Law – every action has an equal and opposite reaction.

In the context of motorsport, when air hits the wing of a racing car, the air may be pushed up but in response, the car is pushed down.

This downwards force is downforce which is the name of the game in the aerodynamic arena.

At face value, all Formula E cars are visually identical, however, when comparing the series’ fully-electric machinery to other single-seater categories, the Gen2 car is radically different.

Behind its futuristic look, the Gen2’s design is based upon aerodynamic efficiency and unlike other championships, isn’t entirely reliant on its wings for downforce and grip.

One of the most noticeable and unique features on the Gen2 is its split-wing design and in 2018, Formula E abandoned the confines of the traditional rear wing.

While this design reduces turbulence and in turn, improves on-track action, it isn’t effective when producing downforce but this is compensated for by the diffuser.

Located at the rear of the car, the diffuser is the Gen2’s main source of rear grip and it improves underbody airflow to reduce drag, increase downforce, and improve efficiency.

But how does it work?

Coincidentally, it stems from the Venturi Effect – the idea air will flow faster if it is forced through a constricted and small area.

For this to happen, the diffuser creates a low-pressure area at the rear and this encourages air to flow under the car between its floor and the ground.

This suction from the diffuser and the low-pressure area then accelerates air through this space which generates a huge amount of downforce in a very efficient way.

At the front, meanwhile, the Gen2’s front wheel fairings reduce drag and turbulent air from the tyres while its defined sidepods channel air outwards to improve overall balance.

Returning to the rear of the car and focussing on airflow, slipstreaming is also a key part of Formula E’s current generation and has become a key strategy influencer.

Slipstreaming is when a driver positions their car directly behind the car ahead, and this tactic means that the trailing car shares air resistance and ultimately, has less drag than the lead vehicle.

This increases the car’s straight-line speed, although, due to the reduced drag, corners become more challenging to navigate as a result of less downforce.

By staying close to the car in front, drivers are able to lift off the throttle earlier than usual without scrubbing off too much straight-line speed.

This means that drivers can lift and coast earlier and ultimately, regenerate and save more usable energy than usual in the heat of battle.

With a set chassis and bodywork, courtesy of Spark Racing Technologies, no wind tunnel testing takes part in Formula E although adjustable wings mean that aerodynamic fine-tuning does take place in the world’s only carbon-neutral racing series.