What Is the ‘Green Paint’ on the F1 Cars?: The Use of ‘Flow Visualisation Paint’ During Testing

Every year, F1 continues to push the limits of modern technology. The advancements they make in this field are beyond extraordinary, and the engineers work hard to do the best for their teams. But the most intricate look at the technological aspects of the sport is seen during the pre-season testing sessions. One such phenomenon has the fans wondering about the fluorescent green stuff on some of the cars. What are these colors? Why are they added to the cars?

That green ‘stuff’ or paint is known as flow-visualization paint or the ‘flow-vis’ as it is known among the teams. The color that looks like paint, is not actually paint. Instead, it is an oily substance that is mixed with fluorescent powder. They are only sprayed on parts of the car, that the team members will keep an eye out for.

What does Flow-vis do for aerodynamics?

To put things simply, the Flow-vis helps the teams keep track of the aerodynamic of the car. Right before going out on the track, they are sprayed on the car. Because F1 cars move at different speeds, and move in different directions all over the circuit, the paint moves.

These movements result in patterns on the car’s chassis, which the engineers then investigate. Upon investigation, the air-flow is  understood in a much better way. Imbalance through the corners, drag in a straight line and other aspects are noted.

In simple terms, the flow-vis is like a wind tunnel for the aerodynamicists. The only difference is that it is out on track and the wind is not being artificially created. The engineers even compare their findings from the wind tunnel to the data gathered through flow-vis.

On the other hand, the flow-vis patterns that are visible to the entire world during testing, so rivals on the paddock can certainly catch a glimpse. If there are geniuses like Adrian Newey out on the track, maybe it could be riskily to use flow-vis.

Can other F1 teams steal aerodynamic inputs?

Well, it is risky. For example, when a team runs their car on flow-vis and gets it back to the garage, the competitors might get an opportunity to click a picture of the car or the patterns made through the airflow.

It is a dream of any competitor to sneak a peek at what their opponent is up to. So if they get successful in capturing an image of the car and understand the flow structure, they can use it for their own benefit. Often, to prevent this, teams use covers to hide the car from the cameras and rival eyes as soon as it has entered the pits.