Formula 1 teams use pre-season testing to extract as much data as possible via various methods - flow-visualisation paint and aerodynamic rakes included.
Both play a key role in every pre-season test - plus some free practice sessions - as a team attempts to learn more about its aerodynamic performance in preparation for the upcoming campaign.
This year is expected to be no different with F1’s 2024 pre-season test on the 21-23 February at Bahrain International Circuit, which also hosts the year’s opening grand prix on the 29 February - 2 March.
Flow-vis is the brightly coloured paint spread across an F1 car’s body part used in pre-season testing or a free practice session. The paint is formed by mixing a fluorescent powder with what’s usually paraffin oil and gets applied to a certain car part when a driver is set to leave the garage. Flow-vis could be applied to a car’s front wing, its sidepod or even all over, but it is especially useful when a new body part has been applied.
Some teams may use a fluorescent paint that can only be seen under an ultraviolet light so rivals cannot look at their data, while another way to do that is by covering the car as soon as it enters the pit-lane.
F1 teams must also be careful with how much flow-vis it applies because too much will cause puddles, whereas too little makes it hard for valuable data to be gathered.
Flow-vis is used to determine aerodynamic performance because, when a car is travelling at high speeds, the paint moves across the body in accordance with the airflow. This leaves lines as the paint begins to dry, meaning it is essentially a wind tunnel but with non-artificial air.
Source: Autosport