F1 tech insight: How Williams tackles cooling in Bahrain

The Williams FW41 features flared exits at the rear of the sidepods, which are significantly wider than what we have seen in testing or during the Australian Grand Prix weekend.

Adequate cooling is one of the first requirements of the Formula 1 car concept when you are putting it together.

If you are not honest with yourself in the early stages of the design, then you will have to suffer the pain in the later stages by making compromises.

It's a lot easier to blank off excess cooling than it is to find more cooling performance from an already tightly-packaged concept, and looking at the Williams it is suffering the consequences of designing its car for a cold day at Silverstone rather than a hot day in Bahrain.

The engine's heat rejection gives you the radiator core area that is required. This, in turn, gives you the radiator inlet size, which is normally about 20% of the radiator core area.

With an outlet area of 30%, you will get a reasonable pressure drop across the radiator core. These areas need to expand uniformly to and from the radiator as they go past all the other restrictions.

After that, you can start to play around. This is what teams call 'uniform body airflow' and it is actually as important, if not more important, than what happens on the outside surfaces.

On the Williams, it seems it has opened up the last bit of the exit area and that further inside the exit duct the clearances on the gearbox etc get smaller.

This will not really do much good for the cooling, and can actually be worse because you can get reverse airflow very easily.

Basically, the airflow at the rear of the car turns inside the duct, actually making cooling worse and the overall car performance very inconsistent.

Williams chief technical officer Paddy Lowe confirmed that the team always planned to run this configuration in Bahrain and it wasn't a reaction to any unexpected cooling demands.

"We are running more cooling at this circuit because it needs it," said Lowe when asked by Autosport about the cooling configuration of the cars.

"The steps we had here we didn't have in Melbourne, we brought them for here but we didn't need them in Australia.

"We're on maximum cooling on one car, but not on the other.

"Different drivers have different driving styles and it tends to drive different temperatures."