A new under-aisle displacement air distribution system for wide-body aircraft cabins

Air quality in aircraft cabins has long been criticized. Current widely-used air distribution systems on airplanes dilute inside generated pollutants by promoting air mixing and thus impose risks of infectious airborne disease transmission. In addition, low moisture content in cabin is believed to be responsible for headache, tiredness and lots of other unknown symptoms. To restrict air mixing while improving air humidity level, this investigation uses a validated computational fluid dynamics (CFD) program to design a new under-aisle displacement air distribution system for wide-body aircraft cabins. The new system supplies fully conditioned outside air at moderate momentum through a narrow channel passage along both side cabin walls to middle height of the cabin just beneath the stowage bins, while simultaneously humid air is supplied through both perforated under aisles. By comparing with the current mixing air distribution system in terms of distribution of CO2 concentration, relative humidity, velocity and temperature, the new system is found being capable of lessening the inhaled CO2 concentration by 30% and can improve the relative humidity from currently 12% to 22% without causing draught risks and moisture condensation on cabin walls.