Hathway E A, Noakes C J, Sleigh P A, Fletcher L A
Pathogen Control Engineering Institute, Department of Civil Engineering, University of Leeds, UK.
Build Environ. 2011 Dec;46(12):2500-2511. doi: 10.1016/j.buildenv.2011.06.001. Epub 2011 Jun 17.
Computational Fluid Dynamics (CFD) is an increasingly popular tool for studying the impact of design interventions on the transport of infectious microorganisms. While much of the focus is on respiratory infections, there is substantial evidence that certain pathogens, such as those which colonise the skin, can be released into, and transported through the air through routine activities. In these situations the bacteria is released over a volume of space, with different intensities and locations varying in time rather than being released at a single point. This paper considers the application of CFD modelling to the evaluation of risk from this type of bioaerosol generation. An experimental validation study provides a direct comparison between CFD simulations and bioaerosol distribution, showing that passive scalar and particle tracking approaches are both appropriate for small particle bioaerosols. The study introduces a zonal source, which aims to represent the time averaged release of bacteria from an activity within a zone around the entire location the release takes place. This approach is shown to perform well when validated numerically though comparison with the time averaged dispersion patterns from a transient source. However, the ability of a point source to represent such dispersion is dependent on airflow regime. The applicability of the model is demonstrated using a simulation of an isolation room representing the release of bacteria from bedmaking.
计算流体动力学（CFD）是一种越来越受欢迎的工具，用于研究设计干预措施对传染性微生物传播的影响。虽然大部分研究重点是呼吸道感染，但有大量证据表明，某些病原体，如那些定植在皮肤上的病原体，可通过日常活动释放到空气中并在空气中传播。在这些情况下，细菌是在一定空间内释放的，其强度和位置随时间变化，而不是在单点释放。本文考虑将CFD建模应用于评估此类生物气溶胶产生的风险。一项实验验证研究对CFD模拟和生物气溶胶分布进行了直接比较，结果表明被动标量和粒子跟踪方法都适用于小颗粒生物气溶胶。该研究引入了一个区域源，旨在表示在整个释放发生地点周围的一个区域内，细菌从一项活动中的时间平均释放情况。通过与瞬态源的时间平均扩散模式进行比较，数值验证表明该方法表现良好。然而，点源表示这种扩散的能力取决于气流状态。通过对一个隔离病房的模拟，展示了该模型的适用性，该模拟代表了铺床过程中细菌的释放。
