MD-11. Fuel system.

Continuing with the systems series for the Rotate MD-11, here a preview of the work done in the Fuel System. A few things are still missing, but for the most part the components, display and logic are operative.

These screenshots show a normal start sequence.

All fuel tanks and relevant compartments have been modeled. Quantity, pressure and temperature for each of them is computed separately. All this data is processed in the custom Fuel System Controller, where logic for most of the sub-systems have been written to simulate most of the system’s functions, including fuel scheduling, cross-feed, CG management, ballast fuel management, anti-ice re-circulation, tip transfer, fuel dump, and abnormal operation. Manual mode, failures and electrical dependencies are also simulated.

Below, shown in the screenshot, the system working with Tail Fuel Management mode active (left); the typical fuel schedule after climb, transferring the fuel from the tail forward (center); and the display during Dump mode (right).

These components have been independently simulated:
– All fuel tanks, including separate outboard and inboard wing compartments.
– 18 fuel pumps.
– 16 valves.
– 5 manifolds.
– 4 fuel feed valves.
– Physical model for fuel flow and thermal behavior.
– Automatic and manual modes.
– Abnormal operation.