Numerical study of transient aircraft cabin flowfield with unsteady air supply

Maintaining a suitable cabin environment for an aircraft at cruise requires constant extraction of fresh air from the engine, resulting in a loss of thrust. An effective air delivery method for ventilating the cabin will minimize such loss and thus improve the fuel economy of an aircraft. This study investigated the unsteady air supply method and found that the averaged temperature and CO₂ concentration levels under periodic air supplies were lower within the whole domain and in typical breath zones than the conventional steady-supply condition with the same amount of fresh air. The dynamic flow pattern observed inside the cabin was found to be the main reason for this improvement. Unsteady air supply has shown great potential in improving the fresh air delivery efficiency and the air quality inside the cabin.