The brake drum, or ‘cake tin’ as you might often hear it referred to, provides a thermal enclosure for the brake assembly so that the airflow isn’t overly influenced by the wheel rim.

With the brakes operating at temperatures near 1000 degrees Celcius, this can be a fire hazard. Air ducts are designed to supply air to cool the brakes while the car is moving, and when it is stationary, you will see the crew use custom blowers to move air through the brake system. In hot climates, dry ice is added to aid the cooling. 

Andrew Burden

The author Kiwi F1 Fan