Determination of particle deposition in enclosed spaces by Detached Eddy Simulation with the Lagrangian method Miao Wang a , Chao-Hsin Lin b , Qingyan Chen a, c, * a School of Mechanical Engineering, Purdue University, 585 Purdue Mall, West Lafayette, IN 47907, USA b Environmental Control Systems, Boeing Commercial Airplanes, Everett, WA 98124, USA c School of Environmental Science and Technology, Tianjin University, Tianjin 300072, China article info Article history: Received 9 March 2011 Received in revised form 13 June 2011 Accepted 15 June 2011 Keywords: CFD Experiment Particle Deposition Indoor abstract Accurate prediction of particle deposition in airliner cabins is important for estimating the exposure risk of passengers to infectious diseases. This study developed a Detached Eddy Simulation (DES) model with a modified Lagrangian method. The computer model was validated with experimental data for particle deposition in a cavity with natural convection and with air velocity, air temperature, and particle concentration data from a four-row, twin-aisle cabin mockup. The validation showed that the model performed well for the two cases. Then the model was further used to study particle deposition in the cabin mockup with seven sizes of particles. The particles were assumed to be released from an index passenger due to breathing or talking at zero velocity and due to coughing at a suitable jet velocity. This study can provide quantitative particle deposition distributions for different surfaces and particles removed by cabin ventilation. Ó 2011 Elsevier Ltd. All rights reserved. 1. Introduction Over four billion people arrive at and depart from airports all over the world every year. This figure will double by 2025, according to a long term traffic forecast (ACI, 2007). Commercial airplane passengers travel in an enclosed cabin environment at close proximity (Spengler and Wilson, 2003). During the long time of air travel, the exposure risk to infectious diseases can be very high. Mangili and Gendreau (2005) evaluated the risk of infectious disease transmission in commercial airplane cabins and concluded that air travel was an important factor in the worldwide spread of infectious diseases. Infectious disease transmission in airplane cabins can occur in many ways, such as direct contact with contagious particles generated from an infected person, inhaling pathogenic airborne agents or droplets, or touching contaminated surfaces. These different disease transmission paths are all closely related to the deposition and transport of contaminant particles or droplets. For example, saliva droplets generated by an index person through coughing or sneezing can deposit directly on the mouth or eyes of another person. The dose of airborne infectious agents and droplets is associated with their deposition rate and transport path, and a surface in an airplane cabin can be contaminated by the trapping of contaminant particles. As the commercial airplane cabins are crowded and packed with different solid surfaces, their influence on particle deposition and transport can be significant. Therefore, it is essential to evaluate the level and distribution of particle depo- sition in a cabin environment. The rapid growth of computer power makes CFD a promising tool for predicting airflows, particle transportation, and deposition in enclosed environments (Spalart and Bogue, 2003; Chen, 2008). For cabin airflow and contaminant transport simulation, Baker et al. (2006, 2008) validated their CFD prediction of air velocity and mass transport inside an aircraft cabin using measurement data. Zhang et al. (2009) measured and simulated gaseous and particulate contaminant transport in a four-row cabin mockup. Poussou et al. (2010) simulated transient flow and contaminant concentration field in a small-scale cabin mockup with a moving body. These studies explored complicated airflow and contamination concen- tration fields inside a cabin environment. However, particle depo- sition on cabin surfaces was neglected in these cases, which could be significant for a crowded cabin environment. Particle deposition has been studied by many researchers, however, for other enclosed environments. Lai and Nazaroff (2000) applied an analogous model for particle deposition to smooth indoor surfaces and predicted a reasonable result for simple * Corresponding author. School of Mechanical Engineering, Purdue University, 585 Purdue Mall, West Lafayette,IN 47907, USA. Tel.: þ1 765 496 7562; fax: þ1 765 496 0539. E-mail address: yanchen@purdue.edu (Q. Chen). Contents lists available at ScienceDirect Atmospheric Environment journal homepage: www.elsevier.com/locate/atmosenv 1352-2310/$ e see front matter Ó 2011 Elsevier Ltd. All rights reserved. doi:10.1016/j.atmosenv.2011.06.042 Atmospheric Environment 45 (2011) 5376e5384