Under the regulations, a drivers stint can be upto 2 ours in length. The existing fuel tank in the car had insufficient volumetric capacity (30L) to achieve this stint length. So, a larger fuel tank was required. The team knew the fuel tank capacity requirement and based upon the space available in the car with the roll cage design, the fuel tank dimensions where determined.
The team then held a series of discussions with Mike Scott at Gulf Sport (http://www.gulf-sport.com) to determine exactly the components that would be needed based upon the Creventic / FIA regulations (eg: tank, aluminum case, pumps, fittings). Gulf Sport are the local agents of Aero Tec Laboratories Inc commonly known as ATL.
The Fédération Internationale de l’Automobile (FIA) is generally accepted as being the world governing body for all motorsport (we exclude North America from that statement) and the FIA defines the specifications and lists the approved products relating to the safety aspects (helmets, race suits etc). The standard by which the complete fuel cell and the auxiliary components must comply is FT3-1999, FT3.5-1999, FT5-1999.
The overall fuel cell comprises of several components and these are detailed in the diagram below:
Internal collector pot:
The collector pot sits at the bottom of the fuel cell with the flaps designed to allow fuel to flow into the collector pot but not out of the collector pot. This ensures the internal fuel pumps have sufficient volume of fuel even under hard corning to supply the engine and prevent fuel starvation. This is especially true when running low fuel levels.
The yellow foam baffles are a specific sponge material that helps reduces the fuel sloshing around the tank under hard acceleration / braking and cornering and suppress explosions.
The team runs two fuel pumps on a 1 duty + 1 stand-by configuration, with each pump having “sock” filters with independent switches on the switch control panel on the dashboard. The pumps are rated to ensure that the fuel is supplied to the engine at the required rate and pressure.
Fuel Level Sensor:
Although the pit wall team calculate the volume of fuel used per lap, the fuel level sensor has been set to illuminate on the dash at a prescribed level. This helps verify the fuel burn rates.
All of the above components fit inside the fuel cell. The cell is designed to contain the fuel and not to split open in the event of a crash. The fuel cell inlet has a non return valve that prevents fuel spilling out of the tank in the event of the car being on its side or up side down.
As per the FIA and event regulations the fuel cell has to contained inside and aluminium container of minimum 2mm thickness with 4 aluminium straps and 40mm wide (2 in each direction across the of the aluminium container) that are bolted to the chassis.
The fuel cell certificate must be visible with a new the cell re-certified after five years by the manufacturer, which if passed is re-certified for a further two years.
The final stage of the installation after fitting the fuel lines and filler, is to box in all the connections, which results in the final installation looking like this: