Under the skin of the Force India VJM09




Hybrid Formula One cars have high cooling demands; the cylinder head and engine oil needs cooling down, but so do the compressed air, gearbox oil, both motor-generator units (MGU-K and -H), the energy store (the battery), etc. In order to optimise airflow circulation on the car's bodywork, F1 engineers always look to keep the size of the radiators to a minimum.

“Every time you can squeeze the bodywork tighter toward the rear of the car, you pick up rear load, which is what we’re always looking to gain,” Force India technical director Andy Green told Racecar Engineering in their November 2016 issue.

“We use the engine cover setup to modify the cooling capacity of the car. We want to run it on the limit and the limit is set by Mercedes. We always want to run right to those limits, we don’t want to be a degree under, because every extra degree that we’re cooling is downforce that we are not generating.”

There is no fan on an F1 car, so the hot air is placed in a low-pressure area (i.e. in the wake of the diffuser). It is the entry/exit pressure differential that makes the air flow through the radiators. That’s why the car overheats when stationary, with cooling relying on speed.

On the top image, one can spot the intercooler placed within the left sidepod and the boost pipework that channels the hot compressed air. Once the intercooler has been removed (see middle picture), another smaller radiator can be seen in the lower sidepod, hence the elbow-shaped tube mentioned in the first page.

On the left-hand side of the bottom image, one can see the gearbox cooler mounted on the carbon casing. It receives cooling air from a specific duct that starts from the air inlet above the driver’s helmet. On the right-hand side is a fan that Force India sets up below the front end when the car is stationary inside the garage. The fan seems to be slotting into an aperture located above the splitter: would it be evidence that part of the control electronics sit below the driver’s legs?