Many racing car systems require some thermal management. The two most commonly discussed are the power unit and brakes; however, many other smaller sub-components can also require some level of intervention. Those include electronic circuits, hydraulic lines and even the driver.

The cooling requirements tend to go against aerodynamic performance, meaning that most often, the intervention to address a cooling requirement will result in a loss of aerodynamic performance (increased drag, reduced downforce or both).

In the context of Formula 1, where the power unit and brake sub-components are cooled passively (i.e. airflow passing through the system without assistance from fans), cooling performance can be improved by increasing the system’s efficiency, its size or increasing the aerodynamic flow rate through the system.

Teams put considerable resources into addressing efficiency by researching new layouts, materials and manufacturing techniques to enhance the heat rejection per unit of volume and mass, essentially attempting to make the system smaller and lighter while retaining its performance.

The flow rate through the system can be adjusted by modifying the cooling system’s inlet and outlet conditions and internal losses. Examples would be placing the inlet in a high-pressure zone and the outlet in a low-pressure zone, making one bigger or smaller. In Formula 1, teams tend to retain the same inlet conditions for the power unit cooling across multiple races and have a range of bodywork options with different exit sizes, which can be used to adjust the system’s cooling level and maximise the aerodynamic performance. Teams also have a range of options for brake cooling, including different inlet scoop sizes and multiple drum flow exit options.

Aerodynamicists and thermal engineers can sometimes have fractious relationships as they push towards different directions. But ultimately, if the car components are not cooled to the required level, the car might not finish the race.

Cooling is a subject that aerodynamicists should embrace from an early design stage.
Well-considered, integrated and efficient cooling systems can unlock a substantial amount of aerodynamic performance.

The following two articles will discuss how the race car’s aerodynamic performance on the track is
analysed and compared to the predictions from wind tunnel and CFD.