n the case of the A380, Airbus’ next generation full double-deck passenger aircraft, simulation engineers faced many new challenges. In its standard version the A380 holds 555 passengers in three classes, on two decks. In theory, a layout holding more than 800 economy class passengers is also possible. It is well documented that Airbus wants to offer airlines and passengers an improved level of cabin comfort and as a result significant demands are placed on the cabin ventilation system.
The ventilation system has to fulfil not only the requirements imposed by the authorities, like minimum air exchange rates or maximum pollutant concentrations, but also Airbus’ self imposed limits like maximum velocity, minimum humidity, etc.In addition, the nature of the cabin flow field has to be designed to ensure the risk for spreading airborne transmitteddiseases is kept to a minimum. Public concern over the spread of Severe Acute Respiratory Syndrome (SARS) during 2003, ensured that aircraft cabin ventilation systems became the focus of public interest.
The fast turn-around times required in the early design stages of large cabin models are often not feasible due to the highamount of cells required to resolve small features like air inlets. In the past, the hardware resources and softwarecapabilities were not always available to run extensive cabin models, which resulted in the problem of “boundary conditionclosure”. Simulating just a slice of the cabin leaves two major boundaries (front & back) in the open. This problem can beaddressed by using no-slip walls, symmetry planes, prescribed in- and outflow or cyclic boundary conditions. However, each solution comes with certain compromises on either the accuracy and/or comparability of results. This is especially true if the area of interest is close to a cabin feature such as the galley, lavatory or, in the special case of the A380, stairhouses. The availability of low-cost CPU power and the release of STAR-CCM+ allowed ICON to approach the problem by creating a complete cabin model for a double deck aircraft seating 484 passengers in three classes.
The ventilation system has to fulfil not only the requirements imposed by the authorities, like minimum air exchange rates or maximum pollutant concentrations, but also Airbus’ self imposed limits like maximum velocity, minimum humidity, etc.In addition, the nature of the cabin flow field has to be designed to ensure the risk for spreading airborne transmitteddiseases is kept to a minimum. Public concern over the spread of Severe Acute Respiratory Syndrome (SARS) during 2003, ensured that aircraft cabin ventilation systems became the focus of public interest.
The fast turn-around times required in the early design stages of large cabin models are often not feasible due to the highamount of cells required to resolve small features like air inlets. In the past, the hardware resources and softwarecapabilities were not always available to run extensive cabin models, which resulted in the problem of “boundary conditionclosure”. Simulating just a slice of the cabin leaves two major boundaries (front & back) in the open. This problem can beaddressed by using no-slip walls, symmetry planes, prescribed in- and outflow or cyclic boundary conditions. However, each solution comes with certain compromises on either the accuracy and/or comparability of results. This is especially true if the area of interest is close to a cabin feature such as the galley, lavatory or, in the special case of the A380, stairhouses. The availability of low-cost CPU power and the release of STAR-CCM+ allowed ICON to approach the problem by creating a complete cabin model for a double deck aircraft seating 484 passengers in three classes.
