A STUDY OF AEROSOL TRANSPORT USING VORTEX METHODS

这笔小额拨款的长期目标是开发一种计算流体动力学模型，以预测工人呼吸区内多分散气溶胶的浓度。本文提出了一项模拟单分散气溶胶输送的初步研究。由于气溶胶在呼吸系统中的沉积位置取决于颗粒的大小和密度，因此这样的预测模型将有助于室内工作环境中的职业暴露评估。具体应用包括：(1)定量判断呼吸区内的颗粒浓度和大小，用于流行病学研究；(2)根据颗粒大小选择适当的个人防护装备；(3)确定加剧或减少暴露在可吸入和可呼吸气雾剂中的风险的人机配置；以及(3)测试局部排气通风系统的设计，以最大限度地减少这些暴露。试点项目将包括编写一个计算机程序来模拟单分散气溶胶在代表工人的钝体附近的传输。将数值模拟的结果与实验数据进行比较，以评估算法的准确性。之前实验的数据已经向调查人员提供。

The long-term objective of this small grant is to develop a computational fluid dynamics model to predict the concentration of polydisperse aerosols within the breathing zone of a worker. A pilot study to model monodisperse aerosol transport is proposed here. Because the deposition site of aerosols within the respiratory system depends on the particle size and density, a predictive model such as this would be useful for occupational exposure assessment in indoor work environments. Specific applications include: (1) quantitative judgment of particle concentration and size within the breathing zone for use in epidemiological studies, (2) selection of the appropriate personal protective equipment on the basis of particle size, (3) identification of the human-machine configurations which exacerbate or minimize risk of exposure to inspirable and respirable aerosols, and (3) testing the design of local exhaust ventilation systems to minimize these exposures. The pilot project will consist of writing a computer program to model the transport of monodisperse aerosols in the near wake of a bluff body representing the worker. Results of the numerical simulations will be compared with experimental data in order to evaluate the accuracy of the algorithm. Data from previous experiments have been made available to the investigators.