Zhang Tengfei Tim, Yin Shi, Wang Shugang
School of Civil and Hydraulic Engineering, Dalian University of Technology (DUT), 2 Linggong Road, Dalian 116024, China.
Build Environ. 2010 Apr;45(4):907-915. doi: 10.1016/j.buildenv.2009.09.010. Epub 2009 Sep 23.
Air environment in aircraft cabins has long been criticized especially for the dryness of the air within. Low moisture content in cabins is known to be responsible for headache, tiredness and many other non-specific symptoms. In addition, current widely used air distribution systems on airplanes dilute internally generated pollutants by promoting air mixing and thus impose risks of infectious airborne disease transmission. To boost air humidity level while simultaneously restricting air mixing, this investigation uses a validated computational fluid dynamics (CFD) program to design a new under-aisle air distribution system for wide-body aircraft cabins. The new system supplies fully outside, dry air at low momentum through a narrow channel passage along both side cabin walls to middle height of the cabin just beneath the stowage bins, while simultaneously humidified air is supplied through both perforated under aisles. By comparing with the current mixing air distribution system in terms of distribution of relative humidity, CO concentration, velocity, temperature and draught risk, the new system is found being able to improve the relative humidity from the existent 10% to the new level of 20% and lessen the inhaled CO concentration by 30%, without causing moisture condensation on cabin interior and inducing draught risks for passengers. The water consumption rate in air humidification is only around 0.05 kg/h per person, which should be affordable by airliners.
飞机机舱内的空气环境长期以来一直备受诟病，尤其是其内部空气的干燥程度。众所周知，机舱内的低湿度会导致头痛、疲劳以及许多其他非特异性症状。此外，目前飞机上广泛使用的空气分配系统通过促进空气混合来稀释内部产生的污染物，从而带来了空气传播传染病的风险。为了提高空气湿度同时限制空气混合，本研究使用经过验证的计算流体动力学（CFD）程序为宽体飞机机舱设计一种新的过道下方空气分配系统。新系统通过沿着机舱两侧壁的狭窄通道以低动量供应完全来自外部的干燥空气，使其到达机舱中间高度、正好位于行李架下方的位置，同时加湿后的空气通过两个带孔的过道供应。通过在相对湿度、一氧化碳浓度、速度、温度和通风风险分布方面与当前的混合空气分配系统进行比较，发现新系统能够将相对湿度从现有的10%提高到20%的新水平，并将吸入的一氧化碳浓度降低30%，而不会在机舱内部产生水分凝结，也不会给乘客带来通风风险。空气加湿的耗水率仅约为每人每小时0.05千克，航空公司应该能够承受。
