james Allen

[maripi]

http://www.jamesallenonf1.com/2013/02/in...sing-well/

Formula 1 cars are prototypes and as such they are constantly changing and being evolved in the pursuit of performance.

The first week of testing in Jerez has seen many teams racking up over a thousand kilometres on their new cars, first working on reliability then pushing new development parts onto the car looking for more speed. But what sort of thing are the engineers looking for and how can they see the difference between a new part that is working and one that is not?

Here we offer a simple example to help readers get a better understanding.

Downforce is crucial in an F1 car and one of the main differences between the cars at the front and those at the back of the grid is the amount of downforce they generate. This is down to having more resources and deploying them better.

Here we are comparing two images of cars where a team has put on Flo Viz paint onto a key aerodynamic part, which highlights the air flow over a key downforce generating piece. Flo Viz is short for “Flow Vizualisation”. It allows engineers to see how a part is behaving aerodynamically.


Marussia brake duct
Look closely at this rear brake duct on the new Marussia car. What you see painted dayglo is what is called a “cascade”, which is a multi element piece on the brake duct which is an important downforce making device close to the rear wheel.

You can see the flow structure; the lower lines aren’t too bad, but as you get to the upper elements the flow moves inboard and separates at the top edge and on the top element the flow has broken down completely.

This cascade isn’t working properly; the geometry is too aggressive and the imperfect flow lines are a clear indication to the team’s engineers that they have work to do in the wind-tunnel. It’s back to the drawing board on this piece for Marussia.


Red Bull

In contrast, look at this photo of the beam wing on the new Red Bull. You can see that the left hand side of the wing has been correctly painted with Flo Viz and the air flow lines are perfect. The air is very attached as it works its way over this piece and this is what engineers want to see when they analyse the flow structure. It means that the wing is doing its job and generating downforce in line with expectations.

Note – The right hand side hasn’t been painted properly which is why it looks a bit strange; this is a mistake by the technician when applying the paint before the run.

Hopefully this gives a better understanding of the kind of work that is going on in Jerez this week and in the remaining tests. If you watch Friday practice sessions at Grands Prix you will see teams doing this too. It’s one of the important jobs of the engineers.

[Technical Analysis - Mark Gillan]